Many "no trespassing" signs say "POSTED" in large letters at the top. Why? Obviously, the sign is posted; that's the whole purpose of a sign. To me, it makes as much sense as putting "ASKED" at the start of a Stack Exchange question or "TEXTED" at the start of a text. Does it serve any legal purpose? Or is it just designed to scare potential trespassers with legal-looking text?
"Posted" is a Term of Art
"Posted" is a term of art in trespass law, specifically meaning that signs forbidding entry have been placed at the borders of a parcel. The page "Properly posted definition" from Law Insider reads:
Properly posted means that signs prohibiting trespass—or bright yellow, bright orange or fluorescent paint—are clearly displayed at all corners, on fishing streams crossing property lines, and on roads, gates and rights-of-way entering the land. Or, they are displayed in a manner that is visible to a person in the area.
The entry "Posting" in the "Legal" section of The Free Dictionary reads:
In connection with Trespass statutes, the act of placing or affixing signs on private property in a manner to give notice of the trespass.
The page "The Importance of Posting Property Signs" reads in relevant part:
Why should you use posted signs on property? Posting property is a great way to let someone know they have entered private land and they might not be welcome. Using posted signs not only indicates trespassing but also can specify restricted activities. Signs are good for both rural and urban settings as a way to protect owners and their property.
Most states have specific rules for property signs that must be followed. Some rules may include:
- Words used: POSTED or NOTICE
- Sign size: 11" x 11" or 144 square inches
- Lettering size: minimum of 2"
- Sign color: purple, bright orange, yellow
- Sign distance: every 100 feet
Some states allow the use of spray paint to mark trees and fences in lieu of a sign. Purple paint is frequently used because it stands out against common natural colors. However, if a trespasser is unaware of this marking method, it would be more effective to use a sign.
Check local and state laws to confirm what is needed to properly post legally in your area.
Several US states use the term "Posted" in their laws on trespass, and provide that the presence of the word "posted" on a sign has special significance.
Maryland Criminal Law Code § 6-402 (2017) provides that:
(a) Prohibited. -- A person may not enter or trespass on property that is posted conspicuously against trespass by:
(a) (1) signs placed where they reasonably may be seen; or
(a) (2) paint marks that:
(a) (2) (i) conform with regulations that the Department of Natural Resources adopts under § 5-209 of the Natural Resources Article; and
(a) (2) (ii) are made on trees or posts that are located:
(a) (2) (ii) 1. at each road entrance to the property; and
(a) (2) (ii) 2. adjacent to public roadways, public waterways, and other land adjoining the property.
The law firm page "Trespassing Laws in Maryland" reads in relevant part:
Posted Property Trespass
A person is not allowed to enter onto property that is posted conspicuously against trespassing. That posting can come in the form of signs that are placed where they can be reasonably seen or by paint marks on trees or posts at the entrances and land adjacent to the property.
The page "Posting Your Land" from the NY Dept of Environmental Conservation reads in relevant part:
Trespassing is illegal even on unposted property. Instead of posting, a landowner or other authorized person may issue written notice to another individual informing them that they are prohibited from entering the property. The notice must contain a description of the property, what restrictions apply (hunting, fishing, trapping) and the person or persons prohibited from entry. It should be delivered by certified mail or other processes (ex: legal notice in newspaper) to prove that the person was served. At any time, anyone by the landowner, occupant, or other authorized person to leave the premises (posted or not), must do so immediately.
Trespassing on areas posted against trespass pursuant to the Environmental Conservation Law is punishable by a fine up to $250 and/or up to 15 days in jail.
It is a defense to this type of trespass that there are not signs posted instructing people to stay off the property. It may also be a defense that any signs posted in the area are not in the proper place to be easily seen by visitors to the property.
Hardware and farm supply stores frequently carry signs for posting. Customized signs may also be obtained from local printers. DEC doesn't provide signs to private landowners unless the landowner is a cooperator under the Fish and Wildlife Management Act. In this case, they will be provided with "Safety Zone" signs. Cooperators provide free public access to most of their property in a large cooperative hunting/fishing area.
Signs must be a minimum of 11 inches by 11 inches. They also must bear the name and address of the owner, lawful occupant or other person or organization authorized to post the area. The sign must bear a conspicuous statement which shall either consist of the word "POSTED" or warn against entry for specified purposes or all purposes without the consent of the person whose name appears on the sign. These words must cover a minimum space of 80 square inches (about 9 by 9 inches) of the sign.
(There is a very similar image included in the Wikipedia article "Trespass".)
In California "Posted property" is the legal term for property where suitable signs have been placed along the boundary or near it, to informa people tht trespassing is forbidden. But it appears that in CA the word "Posted" need not appear on such signs, the words "No Trespassing" being sufficient. California also makes it a misdemeanor (Under section 602) to enter into or remain on property of another, without any legal right to be there, if one is instructed not to enter, or to leave, but such proeprty is not considered "posted".
California Penal Code section 553 provides that:
he following definitions apply to this article only:
(a) “Sign” means a sign not less than one (1) square foot in area and upon which in letters not less than two inches in height appear the words “trespassing-loitering forbidden by law,” or words describing the use of the property followed by the words “no trespassing.”
(b) “Posted property” means any property specified in Section 554 which is posted in a manner provided in Section 554.1 .
(c) “Posted boundary” means a line running from sign to sign and such line need not conform to the legal boundary or legal description of any lot, parcel, or acreage of land, but only the area within the posted boundary shall constitute posted property, except as otherwise provided in subdivision (e) of Section 554.1 .
California Penal Code section 554 provides in relevant part that:
Any property, except that portion of such property to which the general public is accorded access, may be posted against trespassing and loitering in the manner provided in Section 554.1 , and thereby become posted property subject to the provisions of this article applicable to posted property, if such property consists of, or is used, or is designed to be used, for any one or more of the following: ...
California Penal Code section 554.1 provides that:
Any property described in Section 554 may be posted against trespassing and loitering in the following manner:
(a) If it is not enclosed within a fence and if it is of an area not exceeding one (1) acre and has no lineal dimension exceeding one (1) mile, by posting signs at each corner of the area and at each entrance.
(b) If it is not enclosed within a fence, and if it is of an area exceeding one (1) acre, or contains any lineal dimension exceeding one (1) mile, by posting signs along or near the exterior boundaries of the area at intervals of not more than 600 feet, and also at each corner, and, if such property has a definite entrance or entrances, at each such entrance.
(c) If it is enclosed within a fence and if it is of an area not exceeding one (1) acre, and has no lineal dimension exceeding one (1) mile, by posting signs at each corner of such fence and at each entrance.
(d) If it is enclosed within a fence and if it is of an area exceeding one (1) acre, or has any lineal dimension exceeding one (1) mile, by posting signs on, or along the line of, such fence at intervals of not more than 600 feet, and also at each corner and at each entrance.
(e) If it consists of poles or towers or appurtenant structures for the suspension of wires or other conductors for conveying electricity or telegraphic or telephonic messages or of towers or derricks for the production of oil or gas, by affixing a sign upon one or more sides of such poles, towers, or derricks, but such posting shall render only the pole, tower, derrick, or appurtenant structure posted property.
California Penal Code section 555 provides that:
It is unlawful to enter or remain upon any posted property without the written permission of the owner, tenant, or occupant in legal possession or control thereof. Every person who enters or remains upon posted property without such written permission is guilty of a separate offense for each day during any portion of which he enters or remains upon such posted property.
The Vermont Fish and Wildlife Department has a web page about this. If you read the current law you will see the exact wording of the signs is not specified. But in the past, the exact wording of the signs used to be specified in the law. In many states, the word "posted" was required.
I live across the road from a state wildlife management area, and can state from experience that among hunters, "post" means to erect notices on the edge of property that hunting is forbidden, and "posted" is the adjective that describes such property.
To answer the underlying question (not "why is this done" (because it's legally required to, sometimes), but "why is it legally required"), I believe you need to look at the etymology of the word posted.
Posted took on the meaning "to make known", as it referred to the method by which someone made something known - affixing it to a post in a public place:
"to affix (a paper notice, advertisement, etc.) to a post" (in a public place), hence, "to make known, to bring before the public," 1630s
As such, "POSTED" on the sign does not only mean "put on a post" (though it also indicates that!); it means "made known", indicating that a person walking by (a member of the public!) should read it and be aware of its contents.
Beyond that information, there's not a lot out there about the exact reasons some states require(d) or suggest(ed) "POSTED" to be part of the sign.
The presence of the word "POSTED" on a sign means "REGISTERED" and thus may have special significance in locations that prefer this.
This word has many uses to keep the public or someone informed according to many english dictionaries. such as "display (a notice) in a public place"
It may be that explicit proof of signage must be registered in some locations, when it comes to prosecution matters in some counties and may require annual fees.
The absence of the word "posted" also might be insignificant in some states where the contents of rights to privacy, hunting or trespassing is clearly indicated as required. e.g. "posted" is not required in California.
In that context, "POSTED" is not a verb but an adjective.
Additionally, I think these signs typically omit "LAND"; see Posted Land.