The initial GlobeSt.com article indicated that tenant PA Consulting Group has an option for the top three floors of the 17-story tower, a clause that EOP allegedly neglected to address prior to signing Microsoft. The landlord is rumored to be working on a resolution that would include free rent and concessions approaching $10 million, if PA agrees to relocate to another EOP building. But sources tell GlobeSt.com that InterSystems Corp., a tenant of One Memorial Dr. since the prominent office tower opened in 1987, is also threatening legal action.

Not only does InterSystems supposedly hold the second option behind PA for floors 15 through 17, but source familiar with the negotiations explain that the firm had first-refusal rights on most of the other space leased to Microsoft, which inked a 10-year pact at rates said to exceed $70 per sf. One industry professional, also familiar with the negotiations, maintains that EOP considered neither the feelings nor legal rights of tenants who stood in the way of assembling the space needed for Microsoft.

"It was just 'slash-and-burn, let's get it done,'" says the source, who adds that EOP had been advised in advance that there might be encumbrances on the space. Blackstone Group spokeswoman Heather Lucania declined comment on the latest information when contacted by GlobeSt.com. Microsoft also declined to comment, and InterSystems Corp. spokesman Paul Grabscheid says his firm "is not prepared to say anything on the matter at this time." Grabscheid did indicate his firm is focused on remaining at One Memorial Dr. "We have been here for a long time, and we would like to continue to be here," he says. Calls to PA Consulting were not returned by press deadline.