The family of a Pulitzer-winning playwright has filed a copyright infringement lawsuit against director Guillermo del Toro and Fox Searchlight alleging that the Oscar-nominated film "The Shape of Water" is a copy of a 1969 play.

David Zindel, son of American playwright Paul Zindel, filed the complaint on Wednesday alleging that Del Toro's critically acclaimed film has exploited the play "Let Me Hear You Whisper" and should have credited and licensed his father's work, reports theguardian.com.

The allegations, which Del Toro and the studio have denied, were first reported in January. The copyright complaint was filed in California this week, and marks the first legal action the Zindel family has taken against "The Shape of Water".

Recommended Read: Movie Review: The Shape of Water ‘An astutely mounted fairy tale’

"The Shape of Water" is leading the 90th Academy Awards' nomination pack with nods in a maximum of 13 categories. The award ceremony will be held on March 4 at the Dolby Theatre here. It will be aired in India live on Star Movies and Star Movies Select on March 5.

According to theguardian.com, the suit, filed less than two weeks before the Academy Awards, outlines similarities in concept, characters, themes and plot points. "The Shape of Water", co-written by Del Toro and Vanessa Taylor, tells a love story between a mute woman who works as a cleaning lady in a hidden, high-security government laboratory in 1962 Baltimore and a misunderstood aquatic monster.

"Let Me Hear You Whisper", which aired as a TV production nearly 50 years ago, is also about a female janitor in a laboratory who bonds with a sea creature whom she attempts to save.

"The (film) tells a story that is substantially similar, and in many ways identical, to that of the play," David's lawyers wrote in the complaint, alleging "overwhelming similarities" that are "too egregious to ignore". The complaint seeks damages and references the film's earnings of more than $70m at the box office.

David said: "The glaring similarities between the film and our father's play are too extensive for us to ignore and so we had to act".

The complaint was also filed against the novelist Daniel Kraus, an associate producer who has been credited with creating the "original idea" for "The Shape of Water" alongside Del Toro, reports theguardian.com.

In a statement, Fox Searchlight said: "These claims from Mr Zindel's estate are baseless, wholly without merit and we will be filing a motion to dismiss. Furthermore, the estate's complaint seems timed to coincide with the Academy Award voting cycle in order to pressure our studio to quickly settle.

"Instead, we will vigorously defend ourselves and, by extension, this groundbreaking and original film."