At the time of the deal with Asterion, AMP sold a 4% stake in Incubex with the price received prompting a £6.57mln upward revision in the value of the holding.
Revenues over the half-year to September were little changed at £18.1mln (£18.3mln), while there was an interim pre-tax profit of £740,000 (loss £5.4mln).
Net assets rose to £24.9mln from £24.1mln six months earlier.
Richard Burrell, chief executive, said: "AMP continues to make progress and our interim results have benefited from the uplift in the value of our shareholding in Incubex.
“The recently announced 90p per share offer from Asterion represents an attractive offer price for AMP and it ensures that AMP has the right partner to help fund its next phase of growth."
Asterion’s offer values AMP at £63mln.