Genealogical Data Standards: From GEDCOM to Modern Models

Abstract

This paper surveys the common standards for representing, exchanging and archiving genealogical data, beginning with the GEDCOM format introduced by FamilySearch in the late 1980s [1], through efforts to modernize it such as GEDCOM X [2] and GEDCOM 7.0 [3], and on to Semantic Web-based models and RDF representations of genealogy [4][9]. We discuss the structural shortcomings of these formats when faced with families that have intertwined lineages, the question of long-term preservation, and then note, at a high level, the direction adopted by the Nasayeb platform without revealing its implementation details.

1. Introduction: Why Does the "Standard" Matter?

Before any interface or feature, every genealogy system faces a silent but decisive choice: in what data structure do we store the family? This choice determines what the system can and cannot represent, and whether a user's data is portable and durable or locked into a single tool. That is why representation and exchange standards are a cornerstone, not a secondary technical detail [8].

2. Historical Background

GEDCOM (Genealogical Data Communication) emerged in 1984 as a text format for exchanging genealogical data between programs [1]. It adopted a simple hierarchical line-based structure built on numbered levels and short tags, which made it easy to write and parse programmatically and drove its wide adoption until it became the de facto standard in the field. Yet this simplicity came at a cost: loose semantics, divergent interpretations across programs, and the absence of a rigorous formal model [5].

As usage grew, the need for an update arose. FamilySearch introduced the GEDCOM X initiative, which offered a clearer conceptual model, representations in both XML and JSON, and modern web-oriented APIs [2]. In parallel, GEDCOM 7.0 was released in 2021 to address the old ambiguities: standardizing character encoding to UTF-8, tightening media handling, and improving documentation [3]. From another angle, Semantic Web research called for representing genealogy as graphs described with RDF and dedicated ontologies, to ease linking between sources and automated inference [4][9].

3. Where Do Off-the-Shelf Formats Fall Short?

Despite this progress, the implicit assumption in most formats remains biased toward a simple family model: monogamous marriage and a single, clear line of descent. Studies have documented the difficulty of representing non-standard relationships within this framework, including:

• Multiple marriages, where offspring are distributed across several family units that are hard to link cleanly. • Cyclic kinship arising from consanguineous marriage, which introduces "cycles" into the lineage structure that break the tree assumption. • The same individual appearing in more than one position by way of intermarriage, leading to duplication or loss. • Multiple calendars and naming traditions, which many formats treat as edge cases rather than as fundamentals [5][6].

At a deeper level, mathematical anthropology has shown that kinship structures are far richer than these formats capture, and that they are closer to graphs and groups than to trees [7]. In other words, the shortcoming is not a lack of fields, but a shortcoming in the model itself.

A good standard does not impose a shape on the family; it expands to fit the family's shapes.

4. The Problem of Lock-in and Long-Term Preservation

To the structural shortcomings is added a no less important issue: the fate of the data over the long term. Many formats are tied to particular tools or platforms, raising concerns about "vendor lock-in" and the difficulty of moving or recovering data if the tool is discontinued. The literature on digital data archiving has addressed these risks at length and established reference models for long-term preservation, such as the standard OAIS model [8]. From this perspective, it is not enough for a representation to be accurate; it must also be open, documented, and capable of export and migration over time.

5. Why Is Patching Not Enough?

One could have added side fields to an existing format to handle the difficult cases. But patching on top of a foundation that was not built for the purpose bequeaths perpetual fragility and mounting complexity: every exception is handled with a special field, every program interprets it differently, and the interoperability that was the original goal is weakened. The right structure begins with the right model, not with a chain of exceptions.

6. Where Nasayeb Contributes (High Level)

The Nasayeb platform adopts a flexible data model designed from the ground up to accommodate complex lineages, multiple kinship ties, and multiple calendars, while preserving exportability and durability. We limit ourselves here to noting the general principle without revealing the technical details, as this layer represents part of our proprietary work and the advantage we build on. The governing principle is simple at its core: represent the family as it is, not as a simplified template dictates.

We see the real contribution as not merely "a new format," but a design commitment: that tools be built to fit the complexity of real-world families and the particularity of different cultures, including Arab and Islamic ones, rather than confining them to templates designed for a single context. And with the data remaining owned by its owners and exportable, we combine accuracy, openness, and durability.

7. Conclusion

The journey of genealogical standards from GEDCOM to modern semantic models is a story of continuous improvement, but one that has remained captive to a simple family model and to lock-in concerns. The next advance will not come from patching the old, but from rethinking the model itself so that it expands to fit the real-world family in all its complexity, while ensuring the data stays free and owned by its people.

References

1. The Church of Jesus Christ of Latter-day Saints. GEDCOM Standard Release 5.5.1. FamilySearch, 1999.
2. FamilySearch. GEDCOM X Conceptual Model and Serializations (XML/JSON). 2012.
3. FamilySearch. The FamilySearch GEDCOM Specification 7.0. 2021.
4. Zandhuis, I. "Toward a Genealogical Ontology for the Semantic Web." Humanities, Computers and Cultural Heritage, 2005.
5. Campanyà Artés, J., Conesa Caralt, J., & Mayol, E. "Modeling Genealogical Domain: An Open Problem." KEOD, 2012.
6. Bouchard, G. "Population Databases and Genealogical Reconstruction." Historical Methods, 1992.
7. Read, D. "Kinship Algebra Expert System (KAES)." Structure and Dynamics, 2006.
8. Consultative Committee for Space Data Systems. Reference Model for an Open Archival Information System (OAIS). ISO 14721, 2012.
9. Berners-Lee, T., Hendler, J., & Lassila, O. "The Semantic Web." Scientific American, 2001.