e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 Implications of Changes in the Role of Mamak on the Legitimacy of Minangkabau Customary Marriages: A Socio-Legal Study in Rantau and Ranah Irma Fatmawati1. Rahul Ardian Fikri2. Annisa Febrina3 Email: irmafatmawati@dosen. id1, rahulardian@dosen. annisafebrina@dosen. Universitas Pembangunan Panca Budi1, 2, 3 ABSTRACT This study aims to analyze the implications of changes in the role of the 'mamak' on the validity of Minangkabau customary marriages, particularly by comparing practices in the 'ranah' . and in the 'rantau' . In the Minangkabau matrilineal kinship system, the mamak holds a central position as clan leader, decision-maker, and the party that provides customary legitimacy for marriages. However, modernization, social mobility, and changes in family structure have led to shifts in the function and authority of the mamak in various social contexts. This study uses a socio-legal approach to examine how customary norms, religious law, and state law interact in the marriage process, while also exploring how society perceives the validity of marriage when the role of the mamak is no longer dominant. The results show that in the ranah, the role of the mamak remains relatively strong, so the validity of marriage is greatly influenced by the mamak's approval and presence in the customary proceedings. Meanwhile, in the regions, the authority of the mamak . aternal uncl. tends to decline and is often replaced by the biological father, religious figures, or other family figures, without affecting the validity of marriages according to state and religious law. This shift leads to variations in customary practices, potential family conflicts, and renegotiations of the meaning of 'valid' according to adat. Furthermore, it was found that communities make adjustments by recognizing the flexibility of adat as long as it does not conflict with sharia principles, allowing adat to continue in a changing social context. This study concludes that the changing role of the mamak has implications for the transformation of Minangkabau customary marriage practices but does not undermine the legitimacy of marriage as long as the principle of harmonization between adat, sharia, and positive law is maintained. These findings contribute to the development of customary law studies, the strengthening of the socio-legal basis in marriage studies, as well as the understanding of social change dynamics in matrilineal societies. Keywords: Mamak. Minangkabau. Marriage Legitimacy. Customary. Socio-legal. Homeland and Diaspora. INTRODUCTION The Minangkabau people are one of the largest traditional communities in Indonesia that follow a matrilineal kinship system, where lineage is traced through the mother's side. this system, the mamak, the mother's brother, plays a central role as the leader of the clan, guardian of inherited property, family advisor, and the authority in various important decisions, including customary marriage processes. The position of the mamak is not only based on traditional social structure but is also closely linked to the Minangkabau customary philosophy 'adat basandi syarak, syarak basandi Kitabullah,' which reflects harmony between custom, religion, and social norms. However, the times have brought significant social changes. Modernization, e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 urbanization, as well as the increase in education and mobility among the Minangkabau people have influenced the traditional kinship structure, including the weakening of the authority of the uncle in marriage decision-making. Contemporary studies show that Minangkabau customary dynamics have indeed undergone transformations in line with societal For instance. Medaline. Fatmawati, and Nurhayati . found that the practice of resolving customary issues in Minangkabau now requires a more adaptive social approach model because the customary structure is under pressure from social changes. These findings indicate that customary institutions are no longer as strong as they once were in regulating the social life of the community. In addition, changes in the structure of kinship and inheritance relationships also affect the function and position of the uncle . Fatmawati . explains that the development of civil inheritance law and the influence of national law have changed the way society understands family rights and obligations, including in the management of inherited property that was previously the main responsibility of the uncle. This shows that changes in family law orientation contribute to the weakening of the uncle's authority in the modern On the other hand, in the context of homeland and diaspora, the shift in the role of the uncle . has become increasingly apparent. In the diaspora, the Minangkabau people often adapt to a nuclear family structure, so marriage decisions involve more often the biological father or religious figures, rather than the mamak. This situation is also in line with the findings of Fatmawati et al. , which emphasize the need for a restorative approach to maintain customary values amid social changes. This shift in customary authority creates space for new practices in marriage that do not fully follow traditional patterns. The consequences of this change are not only social but also affect legal aspects. Several studies on dispute resolution and the role of customary institutions, such as the research by Siregar et al. , show that communities are now more open to mechanisms for resolving disputes outside of court, indicating a transformation in patterns of authority and social values within customary communities. This can be compared to the dynamics of resolving family issues, including marriage, when customary authority declines. Even in different areas of customary law, such as in studies of Angkola customary criminal law, the flexibility of customary law in interacting with the national legal system is also evident (Fikri. Hartiwiningsih, & Rustamaji, 2. These findings further reinforce that customary law, including Minangkabau customary law, is inseparable from changes in the social structure of In the context of public health as well, the role of mediation and alternative dispute resolution is beginning to be seen as relevant in addressing social issues (Siregar et al. , 2. This illustrates that Indonesian society, including indigenous communities, increasingly prioritizes a flexible deliberation approach that can be adapted to various contexts, including family and marital dynamics. Thus, the changing role of mamak is not only a cultural phenomenon but is also closely related to the dynamics of customary law, interactions with national law, and broader social developments. Therefore, it is important to examine how these changes affect the validity of Minangkabau customary marriages, especially when comparing practices in domains that are more conservative with those in more flexible regions abroad. e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 This study uses a socio-legal approach to understand the relationship between social change and its legal implications. This approach allows for a more comprehensive analysis of how changes in the role of mothers . impact the legitimacy of marriage according to customary law, religious law, and state law. This research is important because it can provide an up-to-date picture of the transformation of the Minangkabau customary structure and its implications for the sustainability of cultural identity in modern society. LITERATURE REVIEW Understanding Mamak In the matrilineal kinship system of the Minangkabau, the mamak plays a central role as a customary guardian responsible for the continuity of the maternal lineage, management of inherited property, and moral oversight of family members. Traditionally, the mamak is not only an authoritative figure in the rumah gadang but also plays an important role in customary decision-making, including in the processes and legitimacy of marriage. Classical anthropological literature, such as the works of Navis. Amir, and Abdullah, emphasizes that the mamak's authority is rooted in the matrilineal structure, positioning him as an intermediary between customs, clans, and the nagari community. However, various contemporary studies indicate significant changes in the role of the mamak, particularly due to modernization, migration, increased education, as well as the development of state law that gives a dominant role to the biological father through the regulations of marital guardianship in Islamic law. In overseas regions, the role of the mamak tends to shift to a symbolic one, while decisions related to marriage are more determined by the nuclear parents or religious institutions. Conversely, in the Minang domain, some customary communities still maintain the mamak's role as a party that ensures the suitability of a marriage according to customary norms, such as clan compatibility, family dignity, and other social This literature generally concludes that although the mamak's authority is still normatively recognized in Minangkabau customs, modern social practices have created new dynamics that affect their legitimacy, function, and authority in determining the validity of a Validity of Minangkabau Customary Marriage The validity of marriage in Minangkabau customs is a result of the combination of customary norms. Islamic law, and social practices that have developed in the community. According to customary law, a marriage is considered valid if it fulfills basic principles such as equality of clans, family consent especially from the woman's side, and the involvement of the mamak as the customary guardian representing the clan. The role of the mamak here is related to social legitimacy, ensuring that the marriage does not violate customary rules such as prohibitions against marrying within the same clan and maintaining family honor. Meanwhile, since Islam has become an integral part of Minangkabau culture, the validity of marriage is also measured based on Islamic legal requirements, such as the presence of a marriage guardian . ali nika. , two witnesses, the ijab kabul . arriage contrac. , and the dowry. Academic works on the Minangkabau, particularly by Navis. Mochtar Naim, and Amir MS, highlight that these two systems do not operate separately but rather complement each other. However, e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 contemporary research shows new dynamics, especially after modernization and state regulation through the Marriage Law and the Compilation of Islamic Law (KHI), which reinforce the role of the paternal guardian . over the role of the maternal uncle. This situation has caused some customary elements to become merely symbolic, such as clan deliberations or the approval of the mamak, even though socially the community still considers them important to maintain harmony and the legitimacy of customs. Thus, literature shows that the validity of Minangkabau customary marriage is a dualistic concept based on the formal requirements of Islamic law and the approval of social customs, so changes in social structure, urbanization, and the weakening authority of the mamak also affect its meaning and implementation both locally and in the diaspora. Homeland and Overseas in the Context of Minangkabau Society The concept of 'ranah' and 'rantau' is an important foundation in the social structure and cultural dynamics of the Minangkabau community. 'Ranah' refers to one's hometown or ancestral land, which is the customary territory where lineage, inherited property, and the matrilineal social structure are preserved across generations. In 'ranah,' customary systems are strong because the authority of uncles, clan leaders, and communal elders remains dominant in regulating social life, including marriage, inheritance, and dispute resolution. Meanwhile, 'rantau' refers to areas of migration, which historically have become a part of Minangkabau identity, where people are known for frequently traveling abroad to seek experiences, education, and better economic opportunities. In the diaspora, customs are still maintained, but they undergo a process of adaptation due to interaction with modern social structures and the demands of urban life. Some literature explains that the authority of the maternal uncle weakens in the diaspora because the position of men as heads of households is more prominent compared to the role of matrilineal kinship, so important decisions such as marriage are more influenced by the nuclear family. Nevertheless, the relationship between the homeland and the diaspora remains strong through kinship bonds, migrant organizations, and customary deliberations that preserve the continuity of Minangkabau values. Therefore, the homeland and the diaspora are not only geographic divisions but also reflect two social contexts that shape the dynamics of customs, family roles, and the legitimacy of Minangkabau culture in modern life. Institutional Transformation Institutional transformation refers to the process of changing the functions, rules, and practices of a social institution, including customary institutions, in response to internal and external pressures. In the study of legal sociology and legal anthropology, institutional transformation is often discussed through the concepts of adaptation, re-legitimization, and norm hybridization, which occurs when customary, religious, and state legal norms interact to produce new patterns of social practice . nstitutional hybridit. This framework is relevant for understanding how the position of the mamak in the Minangkabau matrilineal structure experiences shifts when faced with modernization, overseas migration, and increasingly strong national legal regulations . , the Marriage Law and marriage registration policie. Empirical literature shows several key drivers of institutional transformation in e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 indigenous communities. First, modernization and urbanization change economic patterns and family structures from extended kin-based families to nuclear families, weakening traditional intermediary functions such as the mamak. Second, the migration process . forces the Minangkabau community to adapt to local social norms and laws, making the authority of the kaum more symbolic in migrant environments. Third, the penetration of state law, including formal rules on marriage age, registration, and dispensations, shifts the space for customary decision-making into the administrative and legal realm (Fatmawati, 2020. Medaline. Fatmawati & Nurhayati, 2. METHODS This research uses a socio-legal approach that combines normative analysis of Minangkabau customary rules. Islamic law, and positive law with empirical studies on social practices in both the local community and abroad. This approach was chosen because changes in the role of the uncle . are not only related to the dynamics of custom but also intersect with sharia provisions and state regulations that affect the validity of a marriage. Normatively, the study examines several sources of law, ranging from Minangkabau customary principles that position the mamak as a central actor in determining marriage, fiqh provisions regarding guardians, witnesses, marriage contracts . jab kabu. , and dowries, to the latest Marriage Law, namely Law No. 1 of 1974 as amended by Law No. 16 of 2019. The change in the minimum age of marriage to 19 years for both men and women, the obligation to register marriages as a requirement for administrative validity, as well as the submission of dispensations through the court, are important aspects in understanding how customary marriage practices interact with state law. In addition, the research also considers the latest discourse on revisions to the Marriage Law, which have begun to emphasize the harmonization between customary law, the protection of women, and the strengthening of state oversight mechanisms over customary marriages. Empirically, the research was conducted using a qualitative method to describe the social dynamics developing in Minangkabau society, both in the homeland and in the diaspora. Data were collected through in-depth interviews with mamak, penghulu, bundo kanduang, religious scholars, couples married according to customary law, leaders of migrant organizations. KUA officials, and village or nagari authorities. Direct observation of customary ceremonies, community deliberations, and marriage registration practices was also conducted to observe shifts in the authority of mamak in the context of modern life. Focus group discussions (FGD) were used to understand differences in perceptions across generations and regions regarding the importance of the mamak's presence in determining the validity of a customary marriage. The collected data was then analyzed using thematic analysis, by examining patterns of change, similarities and differences between regions and territories, as well as the tensions that arise between customary norms, religious law, and positive law Source and method triangulation were used to ensure the validity of the data and to provide a comprehensive picture of the implications of changes in the role of the mamak on the legitimacy of Minangkabau customary marriages within the context of evolving legal and social e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 RESULTS AND DISCUSSION RESULT The Legal Position of Mamak in the Minangkabau Kinship Structure According to Customary Norms Governing Marriage Legitimacy Research results indicate that according to Minangkabau customary norms, mamak holds a very important legal position in the kinship structure, particularly regarding decisionmaking and social legitimacy of a marriage. In the Minangkabau matrilineal system, the mamak, who is the mother's brother, acts as the representative of the clan responsible for the children of the family, including determining the suitability of a partner, ensuring customary prohibitions such as marrying within the same clan, and giving customary approval before a marriage takes place. The consent of the mamak is considered a social legitimacy element that determines whether a marriage is recognized by the clan and the customary community. Without the mamak's approval, a marriage may be deemed Auindak buliah adatAy or not meeting customary requirements, even if it is legally valid in terms of religion or state law. Research in the Nagari region of West Sumatra shows that the position of the mamak . aternal uncl. remains strong and often becomes the main determining factor in family At this level, the mamak's role is not only to give permission, but also to ensure that the marriage aligns with customary principles such as bajanjang naiak, batanggo turun, and the integrity of inter-clan relations. In some cases, even the mamak's refusal can lead to delays or the cancellation of customary processes such as batimbang tando. Thus, the legal position of the mamak in the customary context of the region still functions as a formal and moral authority that influences the legitimacy of marriage according to customary views. In the diaspora, this function tends to weaken because people's lives are more influenced by the nuclear family structure and state regulations. Nevertheless, the findings show that the role of the maternal uncle does not entirely disappear, but rather shifts to a symbolic and consultative one. The involvement of the maternal uncle is still considered important for maintaining cultural legitimacy, but the final decision usually lies with the biological parents and the couple who will be married. In some diaspora communities, the validity of marriage is more determined by state registration than by the maternal uncle's approval. This indicates a significant institutional transformation when customary norms have to adapt to modern social and administrative conditions. Overall, the research findings confirm that the legal position of the mamak within the customary structure still has a strong influence on the validity of marriages, especially in the homeland, while in the diaspora its position shifts to become more flexible and adaptive. Nevertheless, customary norms continue to recognize that the mamak has a moral role and authority to give approval, as part of the legitimacy mechanism of Minangkabau customs. The difference in the degree of the mamak's power between the homeland and the diaspora reflects social and institutional changes that affect the application of customary norms in the context of modern marriage. The Changing Role of Mamak Influences the Validity of Minangkabau Customary Marriages in the Homeland and Abroad The changing role of mamak in Minangkabau society also affects the fulfillment of e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 customary law elements that are requirements for the validity of marriage, both at home and In traditional Minangkabau customs, mamak holds a central position as the clan leader, guardian of lineage, as well as the party who gives consent and leads the marriage negotiation Mamak's approval is considered an important element to ensure that the marriage meets customary requirements, including the suitability of tribal origin, family consent, and the customary ceremonial procedures. However, modernization and social shifts in the homeland have weakened the mamak's authority, so marriage decisions are increasingly influenced by the biological parents and the personal wishes of the prospective bride and groom. As a result, the element of mamak's blessing, which was previously decisive, now tends to be symbolic, although in some nagari this element is still maintained as part of the legitimacy of custom. Meanwhile, the change in the role of mamak . aternal uncle. in the diaspora is more significant because the Minangkabau social structure abroad is not as strong as in their The limited presence of mamak, geographical distance, and the lifestyle of nuclear families make the involvement of mamak in the marriage process often only limited to notification or giving informal consent. Many traditional customs are condensed or adapted to the conditions abroad, so elements of customary law that usually serve as requirements for the validity of marriage, such as the involvement of ninik mamak, customary negotiations, and community consultations, are simplified. Abroad, the validity of marriage is more determined by religious provisions and state law, while customary aspects are maintained merely as cultural identity and a form of respect. Thus, the change in the role of the mamak has a direct impact on the fulfillment of the elements of Minangkabau customary law. In the homeland, the change in the mamak's role causes customary elements to be maintained but no longer dominant, while in the diaspora, this role weakens further, making the requirements for the validity of marriage under customary law more flexible and adaptive to the local context. Nevertheless, the mamak still holds important symbolic value as a representation of the matrilineal lineage and as a link between custom and family, even though its practical function in determining the validity of marriage has undergone Differences in Interpretation and Application of Customary Norms Regarding the Role of Mamak in the Marriage Process Between the Minangkabau Community in the Homeland and Abroad The differences in the interpretation and application of customary norms regarding the role of the mamak in the marriage process between Minangkabau communities in the homeland and those in the diaspora arise from differences in social environment, kinship structure, and the level of continuity of customs in both contexts. In the homeland, customary norms are understood more strictly and are passed down through traditional social structures that are still active, such as ninik mamak, penghulu, and the nagari customary institutions. The mamak is seen as an authoritative figure who must provide advice, blessing, and approval in the marriage process, whether in the "maminang" stage, negotiations between clans, or ensuring the compatibility of lineage and ancestry. This more conservative interpretation of custom makes the role of the mamak considered a substantive element in the legitimacy of a marriage, so that without the involvement of the mamak, a marriage can be seen as "customarily flawed" or e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 kinship-wise incomplete. Conversely, in the diaspora, customary norms are interpreted more flexibly because the matrilineal kinship structure cannot be fully implemented. The Minangkabau diaspora communities generally operate within nuclear family units, causing the role of the mamak to shift to being symbolic, advisory, and not always decisive. The application of customary law is adapted to geographical conditions, the limited number of mamak or traditional leaders, as well as the social demands of more individualistic urban communities. In many cases, the presence of biological parents is more dominant in marriage decision-making, while the mamak is only involved to provide approval representatively or online. Customary processes are also simplified, not always conducted through deliberation among the community, and often focus only on ceremonial procedures such as the 'malam bainai' or 'batagak gala. This difference in social context makes the interpretation of customary norms in the homeland more normative and textual, while in the diaspora it is more adaptive and pragmatic. While in the homeland the role of the maternal uncle . remains a symbol of customary legitimacy, in the diaspora, the legitimacy of marriage is more supported by religious and state law provisions, with custom serving as a reinforcement of cultural identity. As a result, the same customary norms are interpreted and practiced with varying degrees of strictness, indicating that Minangkabau customs are not a static system but a social structure that continues to transform according to the context of space and time. The Mechanism of Customary Law Resolution for Disputes over the Validity of Marriage Due to the Shifting Role of Mamak Research results indicate that the mechanism for resolving customary disputes related to the validity of marriage, which arise from the shifting role of the mamak, is handled through a layered approach that combines customary norms, social considerations, and state legal In practice, dispute resolution usually begins at the level of the extended family or clan, led by the mamak and ninik mamak who hold customary authority. Customary deliberations serve to evaluate whether the marriage process has met customary requirements, including the approval of the mamak, compatibility of the clans, and the procedures for interclan negotiations. If there is a discrepancy due to the absence of the mamak's role, the resolution is directed towards restorative efforts such as 'mambaok ka dalam,' re-confirmation of customary rules, or inter-clan reconciliation to maintain social harmony. This approach aligns with the principles of non-litigation dispute resolution that emphasize consensus, as also found in studies on community-based dispute resolution (Siregar et al. , 2. and restorative approaches developed in the context of local customary law (Fatmawati et al. , 2. In overseas areas, the mechanism for resolving customary disputes is more flexible and is often carried out through forums of the immediate family, migrant leaders, or community organizations such as IKMR or FKM. The customary structure being less strong than in the homeland leads to more pragmatic resolutions. the role of the mamak is replaced by community leaders or biological parents in the negotiation process. Customary inconsistencies related to the legality of marriage rarely result in formal customary sanctions but are more often resolved through social agreements or forms of cultural compromise, such as performing additional customary symbolism or consulting with a local penghulu. The role of state law is also more e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 dominant in overseas areas, so the legality of marriage is more often determined by the Marriage Law and administrative marriage registration regulations, while custom serves as a support for values and identity. The socio-legal approach shows that the shifting role of the mamak does not necessarily weaken customary law, but rather encourages changes in the way the Minangkabau community navigates between customary norms, social needs, and formal legal provisions. Dispute resolution mechanisms become a space for negotiation between tradition and modernity, where the legitimacy of custom is maintained through symbolic practices and social dialogue, even within a changed institutional framework. This study affirms that Minangkabau customary law is not a static system, but a normative order that continuously adapts through social practices and interaction with state law. DISCUSSION This discussion shows that the changing role of the 'mamak' in Minangkabau society is not a simple phenomenon, but rather a social transformation process that directly impacts kinship structures and the practice of customary marriage legitimacy. In Minangkabau customary norms, the 'mamak' holds a fundamental position as a senior male from the matrilineal line who is responsible for guiding, protecting, and legitimizing important decisions in the life of their nieces and nephews, including in the marriage process. The legitimacy of marriage under customary law is not only measured by the performance of ritual proceedings but also by the fulfillment of normative elements such as clan compatibility, approval from the community, and the involvement of the 'mamak' as a representative of the lineage. Thus, the legal position of the 'mamak' is not merely a symbol of kinship, but a normative pillar that shapes the authority structure in Minangkabau customary law. However, research results indicate that the role of the 'mamak' has undergone significant shifts due to social changes, community mobility, and the strengthening of the nuclear family in modern life. In regions where traditional structures are still preserved and the customary institutions of the nagari continue to operate, the role of the mamak is still maintained The mamak not only gives approval but also ensures that customary rules are followed so that marriages gain full customary legitimacy. This aligns with the characteristics of indigenous communities that are still oriented towards social harmony and inter-clan Conversely, in the diaspora, the matrilineal structure cannot function fully because people live in an urban context, work far from their kin, and form nuclear families as the main social unit. Kondisi ini membuat peran mamak bergeser menjadi lebih simbolis. persetujuan perkawinan umumnya diambil oleh orang tua kandung, sementara mamak hanya dilibatkan secara formal atau bahkan tidak dilibatkan sama sekali. Dengan demikian, perubahan peran mamak berpengaruh langsung terhadap pemenuhan syarat keabsahan perkawinan adat, terutama dalam hal musyawarah kaum dan representasi garis keturunan. The difference in geographical context between the homeland and the diaspora also results in variations in the interpretation and application of customary norms. In the homeland, marriage procedures are closely related to formal customary structures, such as the role of the ninik mamak, clan consultations, and relatively fixed customary processes. Customary norms are understood more textually and carried out in accordance with traditional rules because the e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 community is still bound by a collective value system. Meanwhile, in the diaspora, there is flexibility in interpretation because the migrant community must adapt to more heterogeneous social conditions and does not always have access to comprehensive customary structures. This leads to a simplification of customary practices, and the legitimacy of marriages is increasingly determined by religious law and state law, such as Law Number 16 of 2019 regarding Amendments to the Marriage Law. Thus, the difference in customary practices in the homeland and the diaspora confirms the dynamic nature of Minangkabau customs, which are capable of adapting to social development and community needs. In the context of resolving disputes over the validity of marriage due to the shifting role of the mamak, the socio-legal approach shows that customary law continues to play an important function, even though its influence differs between the homeland . and abroad . In the homeland, disputes are resolved through restorative customary mechanisms. Community deliberations, mediation by the ninik mamak, and the re-endorsement of customs are carried out to restore social harmony. This process reflects the character of customary law, which emphasizes reconciliation-based resolution rather than formal sanctions. Abroad, dispute resolution is more pragmatic and tends to take the form of family negotiations, consultations with diaspora figures, or other informal social mechanisms. The role of state law becomes more dominant in determining the validity of marriages, while customs are maintained as a flexible cultural identity. Thus, dispute resolution reflects the interaction between custom, religion, and state law, which continues to adapt to the realities of life in the diaspora. Overall, this discussion emphasizes that the transformation of the mamak role is not merely a change in individual function, but a reflection of changes in the Minangkabau social structure due to modernization, urbanization, and migration. A socio-legal approach allows for the understanding that customary law cannot be separated from the social context that shapes Although it has undergone shifts. Minangkabau customs remain relevant because they are able to interact with state law and modern social practices. Therefore, the dynamics of the mamak's position, differences in customary interpretations, and mechanisms for dispute resolution demonstrate that Minangkabau customs are a living law system that continues to evolve with its community. CONCLUSION That the changing role of the mamak in Minangkabau society has significant implications for the legitimacy of customary marriages, both in the homeland and abroad. The mamak, as a central figure in the matrilineal kinship system, traditionally holds a normative and functional role in legitimizing marriage. In the homeland, the position of the mamak remains maintained as a customary authority that ensures all normative elements in the marriage process are fulfilled, from the approval of the family to the formalization of custom. This indicates that customary structures and kinship institutions still function effectively as complementary social systems. However, the social dynamics resulting from migration, urbanization, and the development of nuclear family life in the diaspora have led to a transformation in the role of the maternal uncle. In the diaspora, the role of the maternal uncle is no longer substantively dominant and has shifted more towards a symbolic form, so marriage e-ISSN 2775-2976 International Journal of Economic. Technology and Social Sciences url: https://jurnal. id/index. php/injects Volume 6 Number 2 page 329-340 decisions are increasingly influenced by the biological parents as well as religious and state laws. This phenomenon has led to variations in fulfilling the requirements for the validity of customary marriages, where tradition is no longer the sole basis of legitimacy, but runs alongside the formal legal system. The differences in interpretation and application of customary norms between the homeland and the diaspora show that Minangkabau customs constitute an adaptive legal system, not static, and constantly responsive to social changes. The homeland preserves customs in a more complete form because it is supported by a full customary community structure, while the diaspora exhibits a flexible form of customs adapted to the needs of a more fragmented migrant community. This difference confirms that Minangkabau customs are a living law that continues to undergo adjustments in practice without losing their cultural identity function. In terms of resolving disputes over the validity of marriage due to the shifting role of the maternal uncle, customary mechanisms still operate through a deliberative and restorative approach, especially in the home region. In the diaspora, dispute resolution is more pragmatic, involving family and community leaders of the migrants, and tends to place state law as the primary reference. The socio-legal approach shows that the interaction between custom, religion, and state law becomes the main foundation for re-establishing marriage practices amid changes in the social structure of the Minangkabau community. Overall, this study emphasizes that the transformation of the role of mamak is not a sign of the weakening of custom, but rather a process of adaptation that allows Minangkabau customs to remain relevant. This shift requires a new understanding of the relationship between customary structures, state law, and contemporary social Therefore, this study contributes to enriching socio-legal research on how customary law interacts with social changes, as well as providing a deeper understanding of institutional evolution within Minangkabau society. REFERENCES