The panel explains that Rothschild had failed to advise BT of its obligations once it had acquired 30 per cent or more of the voting stock of Plusnet.

The Takeover Code states that any organisation that acquires 30 per cent or more of voting shares in a company must then make an offer for the rest of the equity capital. Rothschild failed to make BT aware of this at any stage in the transaction.

Eventually the problem was flagged by BT's external legal advisers, and the telco was given special dispensation to sell off enough shares in Plusnet to take it back under the 30 per cent threshold.