Floating authorities visited the floating mystery barge moored to Treasure Island -- and obeyed a secrecy order imposed by the people behind the secret project on the imposing structure, which by all accounts is Web giant Google.
The four-story floating structure may be a data center, a store for Google Glass, or some other "top secret" project, as many outlets have reported over the last week.
PHOTOS: Mystery Google Barge on San Francisco Bay
However, "top secret" is all the Coast Guard will say the barge is, as the agency has "been ordered to remain tight-lipped," according to the San Jose Mercury News.
The Coast Guard visited the barge this week, for unknown and unspecified reasons.
A company called By and Large, which has ties to Google, owns the barge, and lawyers for Google asked for permits for such a structure "months ago," according to the newspaper.
A nondisclosure agreement was signed by the Coast Guard, Reuters reported -- but another Coast Guard spokesman was so reticent he could not even confirm that, the Mercury News reported.
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Only when "the project is completed" can the public agency release information, a Coast Guard spokesman said.
As for when that will be? No loose lips aboard this ship, so it's anyone's guess -- or Google's, mostly.