2026 AskQC office hour member Q&A

13 January 2026

Now that the Library of Congress has decided to stop using form subdivisions, will the authority records for these subdivisions continue to be available in Connexion?

Yes, the Library of Congress has said that the authority records for form subdivisions will continue to be a part of LCSH so they will continue to be available within Connexion and Record Manager since we have a copy of the LCSH authority file. For more information, see the FAQ on omission of $v in LCSH and expanded use of LCGFT, which is provided on LC’s website.

Why aren't those "see also" references in the authority record? (referring to " $x Study and teaching", See $x Instruction and study for music...)

That is an excellent question, but I don’t know the answer. I am sure LC considered doing it as some point, but you would have to ask them why they did not.

So, no one has done the programming to change all of the technically incorrect but still authorized headings? How many years has this been going on? Why bother with it being incorrect if you're going to allow the incorrect ones to authorize?

It’s important to remember that controlling is simply matching authority records. It is in no way a validation of the content or construction. We covered this in our September 2025 Askqc office hours, WorldCat records revealed: The secret lives of validation and controlling. These SHM instruction sheets are very specific and contain many exceptions. It would be incredibly challenging and maybe impossible for a program to be able to recognize when, for example, a heading represents a musical instrument and therefore the free-floating subdivision $x Instruction and study is correct.

Note that “authorized” is a different concept than “controlling headings.” When the SHM talks about a subdivision being “authorized,” that means it is being used appropriately according to instructions. Controlling headings links access points in bibliographic records to authority records.

Are there any plans at OCLC to update this programming in the next few years?

The complex nature of SHM instructions makes it unlikely that we would be able to incorporate them into our controlled headings logic.

Looking ahead to linked data, what parties are working on designing how this type of work will be supported in the future?

There are lots of efforts to support subject access with linked data. Our FAST (Faceted Application of Subject Terminology) project supports a more linked-data friendly approach to subjects because it breaks down what would be a multi-faceted heading in LCSH into separate terms, aka facets. FAST is derived from LCSH, but it is a separate vocabulary. It is easier to apply, but you lose some context. In the future, we may be able to get some of the contextual linking back.

I don’t have an example handy, but I have seen FAST headings with subdivisions.

Yes, there are some FAST headings with subdivisions. One example is geographic headings, e.g., “651 7 Ohio $z Columbus. $2 fast $0 (OCoLC)fst01205076.” There are also some topical terms with subfield $x subdivisions like “650 7 $a Football $x Defense. $2 fast $0 (OCoLC)fst00931378.” You won’t see two different facets like topical and chronological together though.

Does "$x Instruction and study" imply the sort of education that involves actively instructing someone how to do something (playing an instrument) versus the sort of education that involves teaching about a topic? (the history of an instrument) Is that why there's a different subdivision used?

I don’t know the history of this subdivision, but I doubt there was that kind of thought put into it. I suspect what happened is that there were existing subdivisions used under musical instruments, then later there was the free-floating subdivision $x Study and teaching created. At the time this happened, LC might have thought it was too difficult to change all the music subject headings to $x Instruction and study. They might have still been using cards at that point. Also, music cataloging is a specialized area at LC so all the resources about the study and teaching of music would go to the music cataloging team, and they knew which subdivisions to use because they cataloged music all day.

Does anyone know if LC is planning on expanding the LCGFT in light of their decision to stop using form subdivisions? Ex- Children's fiction

LC has said they are reviewing existing form subdivisions and LCGFT to identify gaps. This is discussed in their FAQ document.

22 January 2026

Can you clarify the use of subfield $y (e.g. “XX century”)? Can it only be used after $x History?

Sometimes $y chronological subdivisions are used with $x History (as a free-floating combination), but some areas—such as Art, Philosophy, and Architecture—use the free-floating chronological subdivision without $x History. In other cases, a particular $y is only allowed when established as part of a specific string (i.e., not free-floating). Consult SHM H 1647 (History) and the relevant pattern-heading sheets to determine when to use $x History + $y vs. $y alone.

What is the rationale for treating “classes of persons” separately from ethnic groups, races, and nationalities?

This question is referring to the fact that SHM has these two instruction sheets for free-floating subdivisions: H 1100 Classes of Persons and H 1103 Ethnic Groups (also covers races and nationalities). The SHM does not explain why this was done, so I do not know for certain. My best guess is that there are some instructions at the beginning of each sheet that are specific to one and not the other, e.g., H 1103 has instructions on nationalities that don't apply to classes of persons, and there are some subdivisions in H1103 that are not in H 1110 like $x Colonization. If $x Colonization were in H 1100, the instruction sheet would need to explain all the headings it cannot be used with. But, only someone at the Library of Congress could provide a definitive answer to this question, and they might not know since whomever made this decision no longer works there.

Is there an effort to put “See also” references (e.g., from Study and teaching to Instruction and study in music) directly into subdivision authority records?

Not that the presenter is aware of. Such cross-references would be helpful, but LC has not implemented them in subdivision authority records.

What guidelines exist for entering years in $y—when to use decades, centuries, or year ranges?

Specific chronological subdivisions must be either (a) allowed as free-floating (e.g., via H 1095 for general use or via pattern-heading sheets), or (b) established as part of an authority string. For general history, free-floating options include History—To 1500, History—16th century, … History—21st century. Additional or different chronological breakdowns may be specified in relevant pattern-heading instruction sheets (e.g., Art). If not free-floating or covered by a pattern heading, the chronological subdivision must be established.

Should the 680 scope notes be used when deciding how to apply a subdivision?

Yes—680s are useful, but they often don’t include all constraints. For example, the 680 for Study and teaching looks permissive, but the applicable instruction sheets (H 1095 and then H 2110, which points to H 1160/H 1161 for music) change the choice to Instruction and study for musical topics. Always follow the SHM instruction sheets referenced (e.g., in authority record 073 fields) for the final decision.

Where can I find the relevant documentation in ClassWeb Plus?

In ClassWeb Plus, go to the Cataloging Policy Documents section, open the menu, and then the Subject Headings Manual (SHM).

Is there a link to “pattern heading” information on the QC website?

Yes: Pattern headings for LC subjects on the OCLC help site.

Can you show an example of an instruction sheet?

The panel shared SHM H 1095 (General free-floating topical and form subdivisions) as a PDF example.

Could you talk briefly about the LC deprecation of $v form subheadings, especially as it would affect OCLC records?

Yes, but it's important to be clear about what LC is doing. They are not removing form subdivisions from their authority file. Because we have a copy of LC's subject authority file, including those subdivision authority records, we can continue to control them as part of controlled headings for the many existing and new WorldCat records with LCSH form subdivisions. LC has said they will stop using form subdivisions in bibliographic records for their current cataloging done with the Marva BIBFRAME editor. LC records that are not created with the Marva BIBFRAME editor, like their serial records, will not be impacted by their decision. LC has also not said anything about removing form subdivisions in their existing bibliographic records in WorldCat.

Sometimes, existing WorldCat records are replaced by new LC records. (This depends on the encoding levels of the records and other factors.) Therefore, it is possible that some WorldCat records with LCSH form subdivisions may be replaced by new LC records without them. We are monitoring the situation and will assess the impact on WorldCat data and discovery when LC implements its new policy. If future adjustments to OCLC systems or processes become necessary, we will communicate those changes to our members.

Does OCLC plan bulk corrections/updates for misapplied subheadings?

We do accept suggestions for data quality projects if you would like to email us with a specific suggestion. We are currently working on updating bibliographic records to change $x Study and teaching to $x Instruction and study after some musical instrument headings. However, because there are so many musical instrument headings in LCSH it is hard for us to find all the potentially incorrect the bibliographic records.