The giant squash, having the pseudonym "Giant Pumpkins" for its orange phenotypes. Another pseudonym, "Atlantic Giant," was legally associated with the giant squash in 1986 via a US PVP, and is a 1997-present US trademark. The squash has had numerous pseudonyms associated with it over the centuries. It has gotten larger, from allegedly 200 pounds in the early 1800s, 300 in 1860s, 400 in 1900, and 500 in the 1970s - the squash grew 1,000 pounds in 1995. 1,500 pounds were purported with the passage of another 10 years (2006), and a one-ton fruit was announced in 2012.
A giant pumpkin is an orange fruit of the giant squash C. maxima commonly weighing from 150 pounds to over one ton.
Atlantic Giant is a pseudonym that was legally associated with the giant squash by a 1986 US PVP, and is a 1997-present US trademark. It is a name only, and it is restricted (only since 1997-present). It is not a restriction on the giant squash, and has never been. The current restriction pertains only to agricultural seed, not fruit, and does not specify species.
Not to be confused with Atlantic Giant is “Dill’s” Atlantic Giant, which is a permanent US legal pseudonym for the giant squash when it produces fruit approximately 175 pounds, golden orange, oblong, et cetera, as stipulated by the 1986 PVP. It is a form of the giant squash, but it is not restricted, except that the name must be used if selling it (was restricted 1986-2004). This restriction is the only restriction on the giant squash. If the squash does not closely fit the description of Dill's Atlantic Giant, then it is not Dill's Atlantic Giant.