The logo of Blue Apron is shown on a large sign in front of the New York Stock Exchange before the company's IPO in New York, U.S., June 29, 2017. REUTERS/Lucas Jackson

NEW YORK (Reuters) - Shares of meal-kit service Blue Apron Holdings Inc APRN.O slumped to new lows on Monday in the wake of Amazon.com Inc AMZN.O's move to register a trademark for a possible rival service.

Blue Apron shares tumbled more than 11 percent to $6.51, a drop of nearly 35 percent since its June 29 initial public offering price of $10. The decline came as investors were concerned about its future and the impact of Amazon's planned $13.7 billion acquisition of supermarket chain Whole Foods Market Inc WFM.N amid a fast-expanding meal-kit industry.

In a filing with the U.S. Patent and Trademark Office on July 6, Amazon registered a trademark application for “prepared food kits composed of meat, poultry, fish, seafood, fruit and/or vegetables” that is ready for cooking and assembly as a meal.

Amazon’s planned service is identical to the one offered by Blue Apron, one of the largest meal-kit delivery services in the United States.

Activity in Blue Apron’s options also leaned toward defensive bets, with put options that make money if the shares drop below $5 by the third week of January drawing the most activity on Monday.

Amazon and Blue Apron were not immediately available for comment.

The deal between Amazon and Whole Foods announced in June marks the biggest acquisition for the world’s largest online retailer. Amazon has not said exactly what it would do with Whole Foods’ stores and other assets, but analysts and investors say the deal could upend the landscape for grocers, food delivery services and meal-kit companies.

Last week, the top Democrat in the U.S. House of Representatives’ antitrust subcommittee, David Cicilline, voiced concerns about Amazon’s plan to buy Whole Foods, pushing for a hearing to look into the deal’s impact on consumers.

Amazon shares rose nearly 1 percent to $1010.93 on Monday, up 4.4 percent for the month, while Blue Apron shares were off about 30 percent for July. The e-commerce giant hit an all-time of $1,017 last month.