First-year law students learn legal research using the West Publishing reporters of state and federal court decisions, the West digest system, and Westlaw, an online legal research service. There are alternatives – most states also publish their own appellate decisions, and LexisNexis provides a competing online legal research service – but West began in the 1870s and has long been dominant in this area. One of West’s historical advantages is its digest system.

The West digest system organizes American law through a taxonomy of legal issues consisting of several hundred topics. Each topic is a legal issue, such as Adverse Possession or Civil Rights. Each topic has up to several hundred subtopics, each of which has a number referred to as a key number. For example, topic 95 is Contracts, which has key numbers 1, “Nature and grounds of contractual obligation,” through 355, “Judgment.”

Cases published in the West reporters are analyzed by editors who create sentence-long headnotes that describe points of law referred to in the opinion. Each headnote is given a topic and key number, and the headnotes are listed immediately before the beginning of the opinion. The headnotes are also listed, each with a citation to its case, in multi-volume books called Digests. The headnotes in a Digest are arranged by their topic and key number.

The Digests are a fundamental legal research tool, and headnotes and key numbers are basic components of research on Westlaw. For example, the Seattle office of my firm has in our library the 90-volume Washington Digest 2d, published in 2002. Each volume has a Cumulative Annual Pocket Part, a paperback pamphlet inserted inside the back cover, that covers opinions from 2002 to date. The Washington Digest covers all Washington state and federal cases reported since 1854. Almost all the states have similar sets of Digest volumes published by West, and West also publishes periodically a Decennial Digest, which includes headnotes from West’s entire National Reporter System.

For the lawyers reading this, the foregoing should be well known. But I thought it a useful review, because it shows how thoroughly embedded the West topics and key numbers are in the infrastructure of the U.S. legal system.

Given how pervasive the West topics and key numbers are in our legal system, one can assume that West would change them only when driven to it by necessity. That apparently was the case when West recently revised the LLC topic and the Corporations topic.

West announced a number of changes to its topics and key numbers on March 1. The most significant change from my perspective was that topic 241E, Limited Liability Companies, was deleted. LLCs are now included as part of topic 101, Corporations. The Corporations topic was changed to “Corporations and Business Organizations,” and it now includes LLCs, sole proprietorships, business trusts, and business, trade, and professional associations.

The LLC key numbers have been substantially reorganized. The LLC topic previously included 50 key numbers. Now there are 56, and several now have sub-categories designated as (1), (2), etc. Some key numbers were split into multiple key numbers. For example, under the old system one key number covered “Conversion, merger, and dissolution” of LLCs. Now “Mergers, acquisitions, and reorganizations” are covered by one key number, and “Dissolution and forfeiture” is covered by another, with several subcategories.

The LLC key numbers now break down the subject into much more detail. That presumably reflects West’s recognition of the growth in the number of decisions involving LLC legal issues.

According to Westlaw, here, the new key numbers apply to all cases retroactively. Former key numbers will remain searchable and will continue to exist on Westlaw alongside the new key numbers, but they will be labeled as “formerly.” Researchers using Digests that span the change will have to be aware of the old and new numbers.