A group of owners of cooperative apartments at the Promenade in Bethesda has decided to sue the controversial developer of the complex, American Invsco, in a dispute over property taxes.

The decision was made at a meeting Thursday night of the Promenade Minority Shareholders Association, estimated to represent more than 100 co-op owners at the 1,072-unit high-rise which still has a large number of tenants who were there before the conversion.

The developer will be sued for breaching its fiduciary responsibilities to owners there, owners who participated in the meeting said. They have contended that Invsco undercharged itself for local property taxes and assessed them more than their share. They also say Invsco failed to establish an escrow account for tax funds to insure they could not be used for other purposes.

Invsco only recently became current on property taxes due last September, but the company said it did not pay because the amount of the assessment was in dispute.

Invsco has had financial difficulties, and some owners have feared that if Invsco defaulted on its underlying mortgage there, they would be left with liability on all the firm's debts at the Promenade.

Invsco has said a satisfactory escrow procedure has been established and that no default has been contemplated.

Arnold Schafer, a spokesman for Weaver Brothers, which services the underlying mortgage for Metropolitan Life, also said that no declaration of default has been considered by the mortgagee against Invsco. He said Weaver Brothers is satisfied with arrangements it has made for the establishment of the tax escrow fund.

Before the Thursday meeting, the president of the group and an Invsco representative exchanged charges of intransigence and irresponsibility in negotiations to resolve the tax issues.

Association President Jeffrey Cohen, in a letter dated May 6, said "American Invsco has stalled, stonewalled and reversed position from the day our efforts commenced."

James M. Keane, Invsco executive vice president, countered in a letter of May 12 that Cohen's letter was "irresponsible."