Thanks to a tip from @ZedtheGamer, I encountered the concept of anniversary month in this bit of convolution:
“Anniversary month” means the month in which the anniversary of the limited liability company occurs.
By default it’s forward-looking, but here’s an example where it’s backward-looking, although that’s inconsistent how anniversary is used generally:
“Anniversary Month” means, with respect to any date of determination, the calendar month of the prior calendar year corresponding to the calendar month in which such date of determination occurs.
And anniversary month is also used to mean the month of a subsequent year corresponding to a month (not the month in which a day occurs) of a given year. (For an example of that use, see the last of the examples below.)
The meaning of anniversary year isn’t that complicated, but I recommend you not use it. If I’ve lived to 59 years of age without ever having encountered anniversary month, that suggests it’s not standard. And the economy afforded by anniversary month is modest. So I say the heck with it.
Below are some EDGAR examples featuring anniversary month. In each, anniversary month isn’t used as a defined term. That simplifies matters, but is also ensures that readers will likely spin their wheels just a bit when they encounter anniversary month. In each example, the text featuring anniversary month is in italics and in brackets, and it’s followed by my preferred alternative text, also in italics and in brackets.
The annual Application Service Provider fee shall be payable on the Effective Date and annually during [each anniversary month thereafter] [the month in which the anniversary of the Effective Date occurs].
The first installment shall be paid in accordance with Section 8; thereafter, installment payments shall be paid [in the anniversary month of the date of Termination of Employment] [annually in the month during which the anniversary of the date of Termination of Employment occurs].
The Company will retain the right to repurchase these shares at $0.01 per share purchase price should the Executive experience a termination of employment, as such term is used in the Stock Plan, but this repurchase right will lapse as to one quarter of the total number of shares on the last calendar day of the [anniversary month of hire] [month during which the anniversary of the Executive’s date of hire occurs] each year the executive is employed until fully vested, and shall be subject to the other terms and conditions specified in a separate grant agreement; and
Rent payable pursuant to Section 4.1 above will be adjusted on each anniversary of the Effective Date by a fraction whose numerator is the Price Index published for the then most recent [anniversary month of] [month of that year corresponding to] the first month of the Term and whose denominator is the Base Price Index.
Hasta la vista, anniversary month.