The toughest workplace romance rules in the world?

New rules over office romances are being rolled out at the investment giant BlackRock.

They will now extend to cover dalliances outside the office in a bid to clamp down on conflicts of interest.

BlackRock staff were already expected to tell managers if they were dating one of their 16,000 colleagues.

The new policy, revealed in the New York Post, says staff must disclose relationships with “external partners” who have any connection to the firm.

These will include suppliers and clients of the New York-based firm, which is run by Larry Fink.

The new “updated relationships at work” policy means shining a probing light into the personal lives of potentially hundreds of thousands of people.

The policy says they should disclose any personal relationship they have at any “service provider, vendor, or other third party (including a client), if the non-BlackRock employee is within a group that interacts with BlackRock”, according to an internal memo, seen by the BBC.

The aim is to tackle any conflicts of interest, or perceived conflicts of interest, by taking the matter out of the hands of the employee concerned and allowing human resources and lawyers at the firm assess whether there is a problem.

Three years ago the #Metoo movement, which revealed sexual harassment within a range of professional settings, forced companies to examine their policies on relationship in the workplace. Lower tolerance of relationships between bosses and subordinates have led to the sackings of chief executives at McDonald’s and Intel.

And at BlackRock late last year Mark Wiseman, who had been tipped as a possible successor to Larry Fink, was fired for failing to disclose an affair with a colleague.

The new policy defines which relationships come under the new policy as any that could be “susceptible to perceived impropriety, bias, favouritism, and/or abuse of authority within a work environment”.

That includes not only romantic or sexual relationships, but family connections and outside business interests.

However it adds: “To be clear, however, you do not need to disclose friendships with work colleagues.”

Disclosures would be treated with discretion, but if deemed to be a problem, “alternative work arrangements” may be put in place, the memo says.