Dartmoor, which speaks for 52.46 per cent of its target unless a higher alternative bid comes in, said the offer gave Sphere shareholders 'the prospect of a higher level of income'.
Sphere, run by Marathon Asset Management, noted there was no cash element and urged shareholders to take no action.
Dartmoor, which invests largely in the income shares of other split capital investment trusts, is offering eight new ordinary shares for every 25 Sphere shares, valuing them at 42.7p, compared with 42.5p the day before the bid. There is a separate offer for the warrants.
Dartmoor holds 7.01 per cent of the shares. Two large shareholdings have already been committed to the offer: the 22.94 per cent owned by Abtrust Fund Managers and 22.51 per cent from Exeter Asset Management. Exeter manages Dartmoor.
The offer values Sphere's issued income and residual capital shares at pounds 51.8m and Sphere's issued warrants at pounds 650,000.
One analyst said: 'It appears to be a done deal unless someone comes in with a higher bid.'
Industry sources said it did not appear to be a generous offer.
Sphere also noted the offer did not include offers for the zero dividend shares or the 3.5 per cent cumulative preference shares.
Although it said it was considering other options to its winding- up it has made no formal proposals to shareholders as yet.
In the absence of any alternative proposals the net assets of Sphere would be distributed to the three classes of shareholders.Reuse content