NEW YORK (TheStreet) -- Citigroup (C) made a few new revelations in its annual filing with the Securities and Exchange Commission Friday.

Here's a quick rundown based on a quick read of the 10K.

1. We Got a Subpoena: Citigroup said it received a subpoena from the Civil Division of the U.S. Department of Justice on January 27 in connection with mortgage-backed securities issued, sponsored or underwritten by the bank.

Attorney General Eric Holder had said that the Justice Department had served 11 financial firms with subpoenas in the days leading up to the creation of the new Residential Mortgage Backed Securities Task Force under New York AG Eric Schneiderman.

The bank also said it has received other subpoenas from Federal and state regulators including the SEC on a "variety of aspects of Citigroup's mortgage origination and mortgage servicing practices, including with respect to ancillary insurance products or practices."

While the $26 billion national mortgage settlement on Feb.9 released Citi from a broad range of potential claims, the bank will not receive releases related to securitizations or whole loan sales, nor will it receive releases from criminal, tax, environmental, and certain other categories of liability, it said.

2. Repurchase Claims Jumped: Citigroup has become the target of law firm Gibbs and Bruns, which has representing large institutional investors in their repurchase claims over souring mortgage backed securities (MBS) issued by the big banks and was successful in extracting a $8.5 billion settlement from Bank of America ( BAC) last June.

The bank said it originally received a letter in December from the Houston-based law firm, which said it represented clients holding 25% or more of the voting rights in 35 MBS trusts issued and or underwritten by Citi. The trusts have an aggregate outstanding balance in excess of $9 billion.

The letter alleged that certain mortgages placed in these trusts were sold based on misrepresentations by originators and sellers and that Citigroup improperly serviced the loans in those trusts. The letter threatened to instruct trustees of the trusts to assert claims against Citigroup based on these allegations, the bank said.

More recently, the law firm informed Citigroup that it now represents clients holding the requisite interest in 70 trusts, with an alleged total unpaid principal balance of $24 billion, for which Citi has repurchase obligations.

It is not clear whether Gibbs and Bruns have actually instructed trustees to open an investigation into ineligible mortgages.

So far, the firm has instructed trustees to open investigations into ineligible mortgages in over $95 billion of JPMorgan-issued residential mortgage backed securities. It has also issued similar instructions to trustees over $19 billion worth of RMBS issued by Wells Fargo ( WFC) and $25 billion worth of RMBS issued by Morgan Stanley ( MS).

3. Cybersecurity Threats are a New Risk: Citigroup included a new risk factor in its 10K that cited an increasing risk of "continually evolving cybersecurity or other technological risks which could result in the disclosure of confidential client or customer information, damage to Citi's reputation, additional costs to Citi, regulatory penalties and financial losses."

Citigroup recently experienced a temporary web outage with Brazilian hackers taking the credit. In 2011, the bank saw a major data breach that exposed more than 300,000 customer bank accounts and led to $2.7 million being stolen from 3,400 customers. The bank reimbursed customers for the loss.

Later in the year, Citi Cards Japan said that personal information of more than 90,000 customers had been obtained and sold to a third party illegally.

Despite the new disclosures, Citigroup's estimate of "reasonably possible" losses not yet accrued remained at $4 billion unchanged from its previous estimate.

--Written by Shanthi Bharatwaj in New York

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Disclosure: TheStreet's editorial policy prohibits staff editors and reporters from holding positions in any individual stocks.

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