Appleby's, the international law firm, says on its website that it has recently received enquiries from the International Consortium of Investigative Journalists and some of its media partners about documents that its journalists claim to have seen. This is causing a frenzy in the media, which is anticipating a re-run of the 'Panama Papers' data dump of April last year.

Appleby's site says that the ICIJ's investigation involves "allegations made against our business and the business conducted by some of our clients." The firm is based in Bermuda with offices in the British Virgin Islands, the Cayman Islands, Guernsey, Hong Kong, Isle of Man, Jersey, Mauritius, Seychelles and Shanghai. The data - however much exists - could come from any or all of these places.

Appleby's says that "the media may choose to use [the] information" but refrains from saying that a data dump is inevitable. Nevertheless, compliance officers and money-laundering reporting officers might soon find themselves scanning a new searchable database on the ICIJ website for the background details of existing clients and new applicants for business.

The law firm is at strenuous pains to iterate and reiterate the legality of all its activities at all times. On the subject of protecting its clients' data, it goes on to say that it has reviewed its cyber-security and data access arrangements because of a "data security incident last year which involved some of our data being compromised." It is this data, so far unreleased, that is causing much speculation. Appleby's dismisses it by saying that the ICIJ’s allegations about the information are unfounded and rest on ignorance of the legality of structures that the offshore sector uses, and of other legal points.

Beyond this, little is known. The London Daily Telegraph, leading on the headline "Super-rich fear their financial details will be exposed following Bermuda cyber hack," says that it understands that the leak involves some of Britain’s wealthiest people who are now seeing their lawyers and public relations companies about the legal and reputational risks they might face. The law firm has large corporate customers of many types, including financial institutions, and leaks about these firms could cause the financial services industry some embarrassment also.