What Every Genealogist Should Know ...
About Original and Derivative Records and Primary, Secondary and Tertiary Sources of Information

It is important for genealogists to understand the meaning behind the terms original vs. derivative, as well as primary vs. secondary vs. tertiary source information. Only then can critical evaluations be made of document and the information held within those documents. This knowledge and understanding will help increase the accuracy of research and speed the path toward reaching a defensible conclusion.

In most research occupations, sources of information are generally categorized as primary, secondary or tertiary depending on their originality or their proximity to the source or to the event. In addition to this classification, a document can be labeled as an original record, a copy of the original record, or a derivative record.

Some genealogists have preferred to say that original sources are "based on firsthand knowledge" and that derivative material "is all else." And, in the most very basic terms, there truly is nothing incorrect with this statement. But these two terms alone, are too simplistic to be useful during research and analysis. Furthermore, the terms “original material” and “derivative material” confusingly combine 2 separate conditions. These two conditions are:

1) The physical description of the document
    a. original
    b. copy of original
    c. derivative

2) The state of the information within the document
    a. primary
    b. secondary
    c. tertiary

Below are some examples, which elaborate upon the terms “original sources vs. derivative sources” and “primary information vs. secondary information vs. tertiary information,” their meanings and their usage. I suppose that an entire book could be written on this topic with various more complicated examples, but this article should serve as a decent introduction to the terms. Please note that all names, dates and relationships in this article are fictional.

Basic Definitions. A Starting Point

First, we should have a basic understanding of the various basic meanings of the words, "primary," "secondary," "original" and "derivative." Below are definitions of the adjectival form of each word:

pri·mar·y adj.
1. First or highest in rank, quality, or importance; principal.
2. Being or standing first in a list, series, or sequence.
3. Occurring first in time or sequence; earliest.
4. Being or existing as the first or earliest of a kind; primitive.

sec·ond·ar·y adj.
1.
a. Of the second rank; not primary.
b. Inferior.
c. Minor; lesser.
2. Derived from what is primary or original: a secondary source; a secondary infection

o·rig·i·nal adj
1. Preceding all others in time; first.
2.
a. Not derived from something else; fresh and unusual: an original play, not an adaptation.
b. Showing a marked departure from previous practice; new: a truly original approach.
3. Productive of new things or new ideas; inventive: an original mind.
4. Being the source from which a copy, reproduction, or translation is made.

de·riv·a·tive adj.
1. Resulting from or employing derivation: a derivative word; a derivative process.
2. Copied or adapted from others: a highly derivative prose style.

Simple Examples of Term Usage

The following examples read with a bit of tedium, because many parts of the examples repeat. The repetition, in conjunction with the specific changes made in each example, help to illustrate the use of the aforementioned terms (original record, derivative record, primary, secondary, tertiary)

Primary Source Information

Primary source information is firsthand testimony by one of the people or organizations directly involved in an event or, it can also be direct evidence concerning a topic under investigation. Generally, primary sources of information are recorded or created at or near the time of the event, but this is not always the case. A person's testimony can be a primary source of information if they witnessed, firsthand, a particular event. For instance, John Doe, who was a groom at his own wedding, is a primary source of information about his wedding, because he was present and accounted for during the event. A primary source of information can also be the information held within a document, which represents the first recording of an event. John Doe's original marriage record, signed by him and the officiating party, is also a primary source of information because it was made near or at the time of the event and signed by witnesses to the event.

Some other examples:

1a) If I penned or otherwise recorded a document, which stated "My sons' names are Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992, respectively," then, this record
- is an original record <and it>
- contains primary source material (because the birth information originates from me, the mother, who surely knows the names of her sons and who was surely present at their births).

1b) If I penned or otherwise recorded a document, which stated "My sons' names are Hezekiah and Micajah born, 6 Aug 1990 and 22 Oct 1992, respectively" and someone else makes a transcription or abstract of this statement, and cites the original record, then, the abstract/transcription
- is a derivative record (because it is not the original record penned in my own hand) <and it>
- contains primary source material (because the birth information originated from me, the mother, who surely knew the names of her sons and who was surely present at their births).

1c) If I penned or otherwise recorded a document, which stated said "My sons' names are Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992, respectively" and then someone else makes a photocopy of this original record, and cites the original record, then, the photocopy
- is a copy of the original record <and it>
- contains primary source material (because the birth information originated from me, the mother, who surely knew the names of her sons and who was surely present at their births).

1d) If I penned or otherwise recorded a document, which stated said "My sons' names are Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992, respectively" and then someone else scanned this original record into digital format, and cites the original record, but who then alters or enhances the record in any way, then, the scanned record
- is a derivative record (one which has been subjected to alteration) <and it>
- contains primary source material (because it originates from me, the mother, who surely knows the names of her sons and who was surely present at their births).

Secondary Source Information

Secondary sources of information are always taken or derived from primary sources of information. Secondary sources represent some type of secondhand account (which by the way, can be subject to an individual's interpretation) about an event, a topic, or a person. So, secondary sources end up being based upon something that someone else has experienced and not upon personal experience. Because of this, secondary sources of information will usually represent selected or rearranged material and it is possible that some of it may have been modified. Generally, a secondary source of information is compiled at some later date than that of the original event or the original telling. Secondary sources of information are not written by the participants or by the witnesses to the event described in the source.

Some Examples

2a) A county clerk accepts the original handwritten deposition of my neighbor regarding the births of my sons dated 15 April 2025. The neighbor was not present at the births of my sons, but the deposition included the following statement "My neighbor, Natalie, told me that she had two sons named Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992, respectively." Then, this deposition
- is an original record (of my neighbor's deposition) <and it>
- contains secondary source material (My neighbor was not present at the births of my sons, therefore, the neighbor is providing secondary information, gathered from me, a primary source.)

2b) If someone were to transcribe or abstract the above mentioned neighbor's deposition regarding the births of my sons dated 15 April 2025, and cites the original deposition record, which included the statement "My neighbor, Natalie, told me that she had two sons Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992" then, this transcription/abstract
- is a derivative record (because it is not the original deposition) <and it>
- contains secondary source material (from my neighbor about my sons' births for which the neighbor was not present).

2c) If someone were to photocopy the above mentioned handwritten deposition of the neighbor regarding the births of my sons dated 15 April 2025, and cites the original deposition record, which included the statement "My neighbor, Natalie, told me that she had two sons Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992" then, this photocopy
- is a copy of the original record <and it>
- contains secondary source material (from my neighbor about my sons' births for which the neighbor was not present).

2d) If someone were to digitally scan the above mentioned handwritten deposition of the neighbor regarding the births of my sons dated 15 April 2025, and cites the original deposition record, which included the statement "My neighbor, Natalie, told me that she had two sons Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992" then, proceeds to enhance some portion of the document that may have faded over time, or alters it in any way, then the digital scan
- is a derivative record (enhanced or otherwise altered from the original) <and it>
- contains secondary source material (from my neighbor about my sons' births for which the neighbor was not present).

Tertiary Source Information

Defining a tertiary source of information for genealogical purposes is problematic. One nearly needs to know the exact history of the telling or recording of an event to determine how far removed a source might be from the original or secondary source. Typically tertiary sources of information represent distilled information, collected or summarized from other sources. A genealogical report, which represents the compilation of information from many different sources, is a tertiary source of information. Encyclopedias represent tertiary sources of information. Tertiary sources of information nearly always represent some type of a summary accounting or retelling of an event, a topic, a person, or place that is quite far removed in time and space to the primary source and is generally based on what some other individuals have experienced.

Example:

Consider this scenario, which is based upon the preceding series of examples, and which also probably illustrates the simplest representation of tertiary source information. We fast-forward about 70 years to the year 2060. My sons' birth certificates have been destroyed by a fire, as were all other original, primary source documents surrounding their births. My husband and I, and all other witnesses to the births of my sons, are deceased. My sons have requested help proving the dates of their births and the name of their mother so that they can have a delayed birth certificate registered. Fortunately, the son of my neighbor was present at the time his mother penned her handwritten deposition regarding my sons' births.

3a) The son of my neighbor was present at his mother's deposition at the time she wrote it in 2025 (same deposition as in example 2). The neighbor's son then provides his own handwritten deposition in a clerk's office on behalf of my son, which states "On 15 April 2025, I witnessed my mother write a deposition within which she stated that her neighbor, Natalie, said that she had two sons Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992." This son's handwritten deposition
- is an original record (of his deposition) <and it>
- contains tertiary source material (My neighbor's son was not present at the births of my sons, nor was he present when my neighbor was told about my sons' births. He was only testifying as to what his mother told the clerk about the births of my sons. Therefore, the neighbor's son is providing tertiary information, gathered from his mother, a secondary source, who procured the information from me, a primary source.)

3b) If someone were to transcribe or abstract the above mentioned original handwritten deposition of the neighbor's son, and cites the original record, which included the statement "On 15 April 2025, I witnessed my mother write a deposition within which she stated that her neighbor, Natalie, said that she had two sons Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992," then this transcription/abstract
- is a derivative record (because it is not the original deposition) <and it>
- contains tertiary source material (from my neighbor's son about my sons' births for which neither the neighbor, nor the neighbor's son were present).

3c) If someone were to photocopy the above mentioned original handwritten deposition of the neighbor's son, and cites the original record, which included the statement "On 15 April 2025, I witnessed my mother write a deposition within which she stated that her neighbor, Natalie, said that she had two sons Hezekiah and Micajah, born 6 Aug 1990 and 22 Oct 1992," then this photocopy
- is a copy of the original record <and it>
- contains tertiary source material (from my neighbor's son about my sons' births for which neither the neighbor, nor the neighbor's son were present).

[etc.]

Additional Examples of Term Usage

If you are still awake after all the repetitive detail above, here's another twist to ponder, regarding original records and primary, secondary and tertiary information.

1) Original records can contain primary, secondary and/or tertiary information all at the same time!

Imagine that you are viewing and holding the original death record for Sandra Pittman, who died 22 Jan 2001, in a Chicago, Illinois hospital with her doctor by her side. Jane (Pittman) Fox, daughter of Sandra Pittman, is the informant on the death certificate, although she was not present at the time of death.

Analyzing the document.

1b) Sometimes <gasp!> original records can contain NO primary sources of information!

Using another death certificate example, there are those original records, which also represent the “first records made” and which were made fairly near the time of the event, but which contain no primary source information! These documents include informants who are not in any position to know the facts about the person firsthand. Last year, I researched a case wherein a long lost father was documented for a client - a man who spent most of his life in San Quentin and then finally, the remainder of his life, alone, on the streets. This man's death record, made near the time of his death, indicated he was found under a viaduct on the street, dead approximately "x" hours. None of the information in the document was given by anyone who knew the facts firsthand because no one knew anything about him. On the death record the informant is listed as "information taken from wallet." Parents’ names were “unknown.” By all accounts and purposes it *is* the original record of death for this man ... as original as one is ever going to be. And, it was the first record of this man's death, *regardless* of the quality or quantity of information held within the document. Sometimes original records, as valuable as we generally perceive them to be, may hold something other than primary information and be much less valuable to our research than some other records – original or derivative.

There is one important point which needs to be directly stated here: The genealogical significance, or the “weight,” that a document carries during the course of research is not just determined by whether or not the document is an original record, but whether the sources of information held within the document are primary, secondary or tertiary sources.

2) Derivative records can also contain primary, secondary and/or tertiary information.

Of course, this is a fairly simple example. You or I could abstract the original death record of Sandra Pittman. Then, our transcription is a derivative record. It would consist of the doctor's primary source information regarding the death of Sandra Pittman and the daughter's secondary source information regarding her grandparents' names.

Is it really important to understand this stuff?

It *is* critical that genealogists appraise the merit of each document studied. An appraisal must include an evaluation regarding the originality of the document and then an evaluation regarding the information contained within the document. Sometimes various documents, which purport to record the same event, will conflict with one another regarding some detail of the event. Then, as researchers, we must have the ability to define and categorize documents, so that an analysis can be made of their “weight.” It is important to be able to discern which document holds the information that is most likely to be true, or, which document holds the greater merit, so that research can continue successfully and efficiently. Thus, it is invaluable to know if the information in a document is from primary, secondary, or tertiary sources and whether or not a document represents an original record, a copy of an original record, or a derivative record (an abstract or transcription of the original).

Some sample questions to keep in mind when evaluating a document include:

Returning to the analysis of Sandra Pittman and her parents' names. It is apparent that if my goal were to document Sandra Pittman's parents' names, I would want to evaluate the information in her death record, her obituary, her marriage record and her birth record, presuming all were available to me. With regard to the birth certificate for Sandra Pittman, I'll want to determine whether or not I am actually looking at the original birth document, a photocopy of the original, or an abstract. Was the document made at the time of Sandra's birth and then signed by her mother? Or, was Sandra’s birth document recorded 3 weeks after her birth, by the township assessor, who obtained the information from a midwife? Or, is the birth record a delayed birth, recorded 35 years after the event and deposed by an older sibling?

It is important to do this same type of assessment for each record that is available and then, after working to define what type of documents and information have been gathered, I can begin to compare the documents and evaluate the merit of the information recorded within them ... and then in relation to one another.

Does Sandra Pittman's original birth record agree with the original death record in regard to her parents' names? What if the original birth certificate for Sandra, signed by her mother, says that the parents of Sandra are Raymond Herschel Pittman and Winifred Dei? This information doesn't exactly match that which was recorded in the original death record, but it is close.

So, in order to continue research effectively, we must determine which record is likely closer to the truth. Is it the original birth certificate, signed by her mother that reports correct information, or, is it the death record filled out by Sandra's daughter? With no other variables entering into this equation, then, it is likely that the original birth record of Sandy Pittman, signed by her mother (an original record holding primary source information regarding Sandy's parents) is closer to the actual truth about Sandy's parentage than her original death certificate (an original record holding secondary source information regarding Sandy's parents).

When we define or otherwise communicate to others about the state of a particular document - it is best to first define whether the document is an original record or a derivative one. Then, one can go about describing the quality of the information held within the document. These are two different analyses, which need to be made, so they cannot possibly be effectively defined by the same term.

Taking time to evaluate documents when they are collected and then comparing them one to another will actually help to save time and effort during the research process. Critical evaluations of documents can help clear up conflicting event dates and so that a better insight can be gained into some other individuals who are associated with the family and who were living and present at the time of a particular event. This process will help a genealogist extend a family tree with more authority and speed, because the evidential truth is grasped much sooner in the research process. And, finally, a proper understanding of research terminology and how to define and evaluate a document and its contents can help to reduce or eliminate any tangential research that might result from inaccurate information gleaned from secondary or tertiary retellings of an event.

Natalie Cottrill, author
©2002, All rights reserved

Natalie Cottrill, What Every Genealogist Should Know About Original and Derivative Records and Primary, Secondary and Tertiary Sources of Information, (Online:  ProGenealogists, Inc., 2002), <http://www.progenealogists.com/sourcetypes.htm>