Commas

Q. Can you help me out with a question? Do you use a comma after the abbreviation of the word incorporated? For example, in the sentence “Today, ABC Company, Inc., announced that their earnings have increased 50 percent in the past year,” we have been told to use a comma after the word “Inc.” when used in a sentence. This has caused an uproar within the company because we did not learn this rule. Help!

A. According to CMOS 6.44,

Commas are not required with Inc., Ltd., and such as part of a company’s name. A particular company may use such commas in its corporate documentation; articles and books about such companies, however, should generally opt for a consistent style rather than make exceptions for particular cases.

The trick in running text is that if you use one comma, you must use two.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]