A contentious split between two prominent accounting partners is getting even uglier after a lawsuit filed by one of them has the other pledging to countersue.

Thomas Sponsel, a former partner of Indianapolis-based Greenwalt Sponsel & Co. Inc., filed the complaint, on Dec. 24. Two other former partners, Lisa Purichia and Jason Thompson, joined him in the complaint.

The suit claims Greenwalt Sponsel, now known as Greenwalt CPAs Inc., breached both its fiduciary duty and contract with the three former partners after they left the firm in September to launch a new firm, Sponsel CPA Group.
 
They say Greenwalt Sponsel failed to pay money it owes them pursuant to the firm’s shareholder agreement and instead is offering a discounted value for their stock ownership because they did not give 18 months of notice before they left.

Sponsel and the two partners, though, claim they are due the full amount because the firm granted a waiver to another partner who left without giving the proper notice. They also contend the firm and its managing partner, Larry Greenwalt, forced them to leave early by creating a hostile working environment.

The suit does not specify how much money the former partners are seeking.

 “Rather than waiving the 18-month notice period and paying the full scheduled value as has been done in the past [Greenwalt Sponsel] and [Larry] Greenwalt excluded Sponsel, Purichia and Thompson from partner meetings and communications and took many steps to exclude them from having any meaningful involvement in [the firm], the cumulative effect of which forced them to terminate their employment with [Greenwalt Sponsel],” the lawsuit said.

Greenwalt said Monday morning that he attempted to resolve the dispute through mediation, to no avail, and expects to file a countersuit within the next few weeks.

He said Sponsel violated his shareholder agreement by failing to compensate his former firm for hiring Greenwalt employees.

“The purpose of shareholder agreements is to ensure the firm is not harmed in a long-term basis,” Greenwalt said. “We’re being totally consistent with our shareholder agreements.”

A disagreement over the direction of Greenwalt Sponsel’s succession plan led Sponsel to leave, he said following his exit in September.

Greenwalt acknowledged Sponsel had been expected to succeed him as the firm’s leader in January 2011. But he said Sponsel failed to deliver on certain commitments and even contemplated leaving the firm.

Sponsel and Greenwalt, who is a defendant in the lawsuit, had worked together for nearly 30 years. They both started at the former Keller Gaughan & Greenwalt accounting firm in 1980. They changed the name to Greenwalt Sponsel in 1987.

Before Sponsel’s departure, Greenwalt had 31 certified public accountants and 59 full-time employees, ranking it as the 11th-largest accounting firm in the city, according to the most recent IBJ statistics. Sponsel took at least three partners with him.

He is leasing 10,000 square feet of office space at the Gateway Plaza building at 950 N. Meridian St.