The C.I.A. acknowledged that the dates of Ms. Wilson’s employment had mistakenly been disclosed, although a spokesman said that did not mean the information was no longer classified.  “Frankly,” said the spokesman, Mark Mansfield, the release of the information in 2006, in response to a query from Ms. Wilson about retirement benefits, was “an honest-to-goodness administrative error.”  “The letter contained classified information and should not have been mailed to her,” Mr. Mansfield said, referring to Ms. Wilson. “As soon as it was discovered, we took steps to rectify the error, including notifying the clerk of the House of Representatives.”  The letter, from February 2006, was entered into the Congressional Record by Representative Jay Inslee, Democrat of Washington, in January 2007. Mr. Inslee was introducing legislation to allow Ms. Wilson to qualify for a government annuity.  The letter said that Ms. Wilson had worked for the government since Nov. 9, 1985, for a total of “20 years, 7 days,” including “six years, one month and 29 days of overseas service.”  Christine Hanson, a spokeswoman for Mr. Inslee, said the congressman had assured himself that the document was not classified before disclosing it.  “It’s very much part of the public domain,” Ms. Hanson said. “If they’re upset about it, they should have made that determination before they gave the letter to her. They’re trying to get the cat back into the bag.”  Since the publication of the letter in the Congressional Record, the C.I.A. has repeatedly demanded that Ms. Wilson return all copies of it.  The agency receives about 100 submissions a month from former employees and others who have had access to classified information, Mr. Mansfield said, ranging from short opinion articles to lengthy books. “The sole yardstick for prepublication review,” he said, “has been and remains that their writings contain no classified information.”  The C.I.A. has been adamant in refusing to confirm the dates or details of Ms. Wilson’s service before 2002. In July 2003, the syndicated columnist Robert Novak disclosed her identity as “an agency operative on weapons of mass destruction.” Mr. Novak referred to Ms. Wilson by her maiden name, Valerie Plame.  The investigation into that disclosure led to the conviction of I. Lewis Libby Jr., formerly Vice President Dick Cheney’s chief of staff, on perjury and obstruction of justice charges in March.  On Friday, the special prosecutor in the case, Patrick J. Fitzgerald, submitted an unclassified summary of Ms. Wilson’s “C.I.A. employment and cover history” to the judge who will sentence Mr. Libby.  It was limited to the four years starting in 2002. In the summary, the agency said it chose to make information about Ms. Wilson’s service public to aid Mr. Fitzgerald, but it did not say why it selected 2002 as its cutoff. A trip undertaken for the C.I.A. in February 2002 by Joseph C. Wilson IV, a former diplomat and Ms. Wilson’s husband, has been the subject of intense scrutiny.  The summary said that Ms. Wilson was a covert C.I.A. employee at the time of Mr. Novak’s disclosure. Between the beginning of 2002 and Ms. Wilson’s resignation from the agency at the end of 2005, the summary said, she traveled overseas “under a cover identity, sometimes in true name and sometimes in alias” at least “seven times to more than 10 countries.”  The summary said that the C.I.A. did not acknowledge “any other period of employment, if any, nor does it declassify the nature and details of Ms. Wilson’s cover.”  Through a spokesman, Ms. Wilson declined to comment.  Asked if the dispute over the dates of Ms. Wilson’s tenure were the key to allowing the book to be published, an intelligence official responded obliquely.  “Official acknowledgment of certain matters could cause some on whom we rely to think that we do not take protecting sensitive equity seriously or cause them to think twice about assisting us in the future, and that could have serious ramifications,” the official said.  In an April 19 letter, the lawsuit said, the agency said that “with limited exceptions” the classified information to which the agency objects “relates to a single issue,” although it did not specify the issue.  Mr. Rothberg, of Simon & Schuster, said the dates of Ms. Wilson’s service were “just one item in the publication review process, but it’s one we feel strongly about.” The publisher is said to have paid about $2 million for the book, a figure Mr. Rothberg would not confirm.  A version of this article appears in print on , on Page A18 of the New York edition with the headline: Agent in Leak Case Sues C.I.A. for Blocking the Release of Her Memoir. Order Reprints| Today's Paper|Subscribe
The former intelligence operative sued the Central Intelligence Agency over its refusal to allow her to publish a memoir that would discuss how long she had worked for the agency.