Thornburg shares rose 73 cents, or 32.4 percent, to close at $2.98 Tuesday. The stock has plunged from a 52-week high of $28.40 last May to a low of 69 cents last week.

Thornburg disclosed the agreement in a Securities and Exchange Commission filing Monday.

Previously, Thornburg said it might be forced to sell assets to raise capital to cover default notices and margin calls on some of its financing agreements.

Margin calls force borrowers to repay loans or put up more collateral to secure them. If a borrower is unable to meet the calls, the creditor typically can seize and liquidate assets used as collateral.

The company notes there is no assurance that it will be able to obtain sufficient liquidity to satisfy its liabilities and continue as a going concern.