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President Obama's declaration that the Boston Marathon bombings were an act of terrorism could make it difficult for many businesses that sustained damage and lost revenue in the attack to be reimbursed for losses resulting from the explosions.

Federal law enacted after the 9/11 terrorist attacks requires the government to certify whether an act of terrorism has occurred for businesses to determine liability for losses. If a business did not buy specific terrorism coverage an official designation could make it harder to get reimbursed.

The Boston Globe reported Saturday that many small businesses on Boylston Street did not buy terrorism coverage.

Most business losses resulted from closing Boylston Street as a crime scene, not the April 15 blasts that killed three and injured more than 260. Proving a loss requires tallying receipts from a previous comparable period to demonstrate the cost of being shut by authorities.

"A lot of businesses in the Back Bay will be greatly harmed if they do declare it terrorism," said Chris Jamison, owner of Lolita Cocina & Tequila Bar near the corner of Dartmouth and Boylston streets. "I basically would have no plan whatsoever."

Jon Cowen, a lawyer and insurance specialist who has been consulted by the Menino administration on coverage issues, said there are more questions than answers about the issues involved.

"The bottom line is that it's doubtful we will know very soon whether this will be treated as terrorism," he said.

Within the Obama administration, the decision will be made jointly by the Treasury Department, Secretary of State John Kerry and Attorney General Eric Holder. The law does not set a deadline.

Boston Mayor Tom Menino told reporters at a press conference Saturday that he has confidence Obama will not sign anything that would hurt businesses impacted by the bombings, MyFoxBoston.com reported.

"He won't sign anything that would hinder them from collecting insurance or any other benefits," Menino was quoted as saying.

An analysis by Marsh & McLennan New England, a division of the insurance company, said small to medium-sized businesses paid about $49 per $1 million of insured value in 2012. For small businesses, such coverage ranges from a few hundred dollars a year to several thousand, which could be too high as businesses budget for other expenses.

Business owners and their employees are restocking supplies, fixing broken equipment and helping employees with lost wages, traumatic memories and, in some cases, injuries.

"I don't think anybody is really back to normal yet," said Dan Donahue, managing director of the Lenox Hotel. "I think we're going to be covered either way. But everybody is holding their cards very close to the vest right now. For the small businesses around us, you sort of hope it's not determined to be terrorism."

David Sapers, owner of candy store Sugar Heaven, told MyFoxBoston.com he took a risk by not purchasing terrorism coverage.

"This is a terrorism act, and we're not [going to] change the rules because people want to recoup money from the insurance companies," Sapers told the station.

Click here for more from The Boston Globe.

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