Trillium Asset Management leads the way with several investors. StarbucksTo have a neutral global policy for any current or future efforts of workers to organize. The union members also demand that Starbucks reach fair and timely collective bargains for workers who have voted to join it.

In a letterThe coalition of over 75 investors, including Kevin Johnson, Starbucks CEO, and Mellody Hobson Chair, warn of reputational risks for the coffee giant. They cite growing support from the public for unions.

This outreach takes place ahead of Starbucks’ annual shareholder meetings on Wednesday. Signatories include Trillium Investment Group, Parnassus Investments as well as Brad Lander, New York City Comptroller, Parnassus Investments. According to the group, it has at least $1.2 Billion in Starbucks stock. It is also the largest shareholder of Starbucks stock. second such letterThe group stated that it had sent the message to the CEO.

We believe that Starbucks’ response to the union organizing activity suggests it has abandoned international norms, standards and its promises to them. “Our concerns concern Starbucks’ behavior at shops that organized following the Buffalo election, such as the alleged termination of employees in retaliation and continuing captive audience meetings,” says the letter.

Starbucks didn’t immediately reply to our request for comment.

There have been more than 130 Starbucks stores in 26 statesAccording to Starbucks Workers United organizers, they petitioned for the National Labor Relations Board (NLRB) to organize. The elections were held in seven of the stores. six cafes have sided with the union. The Buffalo market in New York has five of these locations. Unionization efforts started last summer in New York. One cafe is located in Mesa in Arizona.

Starbucks maintains that the marketwide vote is more appropriate than single-store counts to ensure that workers can participate. The NLRB rejected this premise.

Starbucks Workers United has accused Starbucks of union-busting and retaliation. The company denies the allegations. According to the organizers, they filed a NLRB unfair labor practice case. The charge claimed Starbucks had reduced workers’ hours and imposed financial penalties for supporting the union.

The company spent many decades working on improving its ESG profile and building its reputation for environmental, governance, and social factors. “We are very concerned that they put their reputation at risk,” Jonas Kron (chief advocacy officer at Trillium) said in an interview to CNBC.

Lander, New York City’s Comptroller stated, “Now, they have to decide, they can choose to keep on a path to respecting their employees by allowing fair and free elections by adopting this neutrality policy… but they risk losing all that goodwill which they’ve built over time.”

According to the coalition, respecting the union is best for Starbucks’ productivity and growth.

Companies and employees both gain when worker rights are respected, represented, and their concerns communicated. The investors wrote that they see benefits such as lower turnover, risk tolerance, greater employee satisfaction and productivity and ultimately, improved products and services.

CNBC spoke with Dieter Waizenegger about the choice that customers face. “The company needs to work extremely hard to ensure that its people-positive reputation is maintained, and that its partners are a partner of itss,” Dieter Waizenegger, executive director at SOC Investment Group said to CNBC.

Starbucks shares fell by more than 4% on Monday. They are also down 32% for the year.