The en:Shahada in white calligraphy on a green background. Reported as the "Flag of  Hamas" in flaggenlexikon.de . Uploaded 2007.
The Flags of the World website discussed the validity of this flag after it was displayed as an alleged "flag of Hamas" by Wikipedia in 2007.
According to a 2006 comment:

"The military branch of Hamas has a different flag, green with Shahada on it. Maybe that's why there is a confusion about the Hamas flag. One is white with Hamas emblem on it, and the military branch's flag is green with a shahada? At least, the green flag is there at all protests and demonstrations."  (Valentin Poposki, 03 Mar 2006)Use of this flag was reported as early as 2001:

"Hamas' flag is green (Muslim colour) with Arabic words in white. I saw this flag several times at Hamas demonstrations and at generic anti-Israel events in Palestine. Hamas emblem is here." (Santiago Tazón, 20 Dec 2001)While this flag has apparently been spotted in Hamas demonstrations since at least 2001, it cannot be identified as "the flag of Hamas". It has rather been carried by Hamas supporters as symbolizing Islam or Islamism, not as an emblem of Hamas as an organization.

"It would be wrong to name the flag as the Hamas flag. Such flags, with the Sha'ada in white on green or black, are used by other Islamic groups and are not unique to Hamas. Therefore it is not the 'Hamas flag' but rather a flag used also by the Hamas." (Dov Gutterman, 29 Mar 2003)
self-made, based in Image:Hamas flag2.png
Guilherme Paula, Oren neu dag