This is making the rounds on social networks:
DID YOU KNOW
Over 20 Navy SEALs who (allegedly) "killed" Osama Bin Laden are now dead.
Is there any truth to this (today as in 8 May 2015)
This is not true.
In August 2011, 38 people died in a single helicopter crash, including 15 members of NAVY SEALs' Team 6. The accident has been described as "the worst battlefield calamity in [the team's] history". A U.S. Boeing CH-47 Chinook military helicopter was shot down while transporting a quick reaction force attempting to reinforce an engaged unit of Army Rangers in Wardak province, west of Kabul, Afghanistan. This is what the above image and caption is referring to.
We do not know the exact makeup of the team that killed Osama, however according to official sources:
All but two of the SEALs [killed in the crash] were from SEAL Team 6, the unit that killed Osama bin Laden, although military officials said none of the crash victims was on that mission in Pakistan against the al-Qaida leader.
The image above has used a photo collage from this article, which also contains the above quote. Confirmation of this can also be found in a report by CNN, BBC, NBC and in other sources. Specifically, an article in USA Today explains that the men killed belonged to the Gold Squadron, while the soldiers involved in the assassination belonged to the Red Squadron. Team 6 has four line squadrons: Blue, Gold, Red and Silver, plus a reconnaissance unit known as Black Squadron. Furthermore each squadron is divided into three troops. The crash wiped out an entire troop in Gold Squadron.
TL;DR The image above represents people who have died in a helicopter crash, a lot of them were members of SEAL Team 6 but none of them was involved in the assassination of Osama.
Moreover as Philipp pointed out in the comments, SEAL Team Six (United States Naval Special Warfare Development Group) isn't a small group and has roughly around 200 people amongst its ranks.
Like most conspiracy theories, this claim is unfalsifiable.
The identities of the SEALs involved in the assault on Bin Laden's compound were not released to the press or the public -- in fact, the one time FOX News attempted to out one of them they caught a great deal of flak over it.
Those identities are classified information, and without knowing who they are it's pretty much impossible to conclusively state whether any of them are alive or dead.
Of course, conversely, the person who made this claim is working from the same lack of information - if he or she is capable of conclusively stating that 20 of them are dead, he or she would have to know their identities first... In which case they have access to highly classified information and probably shouldn't be spouting it on the internet as a meme.
So in conclusion, either the originator of the claim is ignorant and made it up out of whole cloth, or they're not and essentially committing treason.
The fact that (as MMM points out) they're using an image that pertains to an unrelated incident certainly indicates the former, but either way this isn't answerable without more information than the people on this site are likely to have access to -- and even if any of us did, we'd be legally bound to deny having it.