Wyoming prescribes a form for each notice in chapter 10 of title 29, defines "sent" as deposit in the mail, and attaches different consequences to each: the preliminary notice bars the lien when late, the notice of filing does not affect the lien at all.
The preliminary notice of right to lien (29-2-112)
"The contractor, subcontractor and materialman shall send written notice to the record owner or his agent" — subcontractors and materialmen "within thirty (30) days after first providing services or materials to the construction project", a contractor "prior to receiving any payment from owner, including advances" (29-2-112(a)(i), (ii)). Each subcontractor and materialman also provides a copy to the contractor it works for (29-10-101(a)).
"Failure to send the notice required under this section within the time specified shall bar the right of a contractor, subcontractor or materialman to assert a lien" (29-2-112(a)(iii)). The form is 29-10-101, and it states that a form of lien waiver is attached — 29-10-101(b) supplies that waiver form.
The notice of intention to file lien (29-2-107)
"Before filing a lien pursuant to this chapter a lien claimant shall send written notice to the record owner or his agent of any claim against real property, a building or an improvement stating the amount of any claim and from whom it is due. The notice shall be sent no later than twenty (20) days prior to filing a lien statement" (29-2-107(a)), in the form of 29-10-102 — headed CERTIFIED MAIL, RETURN RECEIPT REQUESTED, one form for each owner. The lien statement itself is filed within 150 days (a contractor) or 120 days (everyone else) of the earlier of the last work or materials or substantial completion (29-2-106(a)).
The notice of filing lien (29-1-312(c))
"Notice shall be sent by the lien claimant to the last record owner or his agent in the case of a real property lien within thirty (30) days after the lien statement is filed", in the form of 29-10-103 — also headed CERTIFIED MAIL, RETURN RECEIPT REQUESTED. The same subsection adds: "Failure to send the notice required under this subsection shall not affect the validity of the lien."
"Sent" means deposited
"Send" or "sent" means "to deposit in the mail or deliver for transmission by any other usual means of communication with postage or cost of transmission provided for and properly addressed" (29-1-201(a)(xii)) — the clocks above run to the day of deposit, not receipt. Where a form is headed "return receipt requested", the receipt is part of the method and is included.