The sale of senior notes by The Blackstone Group, which raised $600m (€420m) yesterday, was the largest corporate debt offering by a private equity firm in more than two years, according to data from research provider Dealogic.

A source familiar with the private placement said the firm raised $600m through 10-year notes. At 6.625%, the notes yielded 312.5bps more than treasury securities of comparable time horizon, said the source.