Earlier this month a WTO dispute panel found the US had dealt with all but one of the instances of illegal subsidies to the aerospace giant.
But Airbus maintains the US continues to offer unfair support.
The fight is part of a 13-year dispute between the EU and the US over support offered to Boeing and Europe's Airbus.
In 2012, the WTO found that state and federal programmes provided Boeing with billions of dollars in illegal subsidies.
On 9 June the WTO's dispute panel found most of those issues had been addressed.
However, generous tax benefits offered by the state of Washington, where Boeing has a large presence and which are worth an estimated $800m to date, continue.
Both sides claimed the panel's June findings as a victory.
The WTO has also found that Europe provided billions in illegal subsidies to Airbus.

The YouTuber, who has more than six million followers, is taking a break from her online world "for a few days" because she says it is "clouding up" her brain.
The news comes the same week that she admitted she had "help" from her publisher in writing her debut novel, Girl Online.
Zoella "worked with an expert editorial team" said a spokesperson from Penguin.
It also said it was part of a publisher's role to "help" new talent.
Zoella's boyfriend, Alfie Deyes, has also said he is quitting the internet and thanked fans for their "understanding".
He said the pair plan "to have some time to ourselves" during their break.
Earlier this year Alfie, who runs Pointless Blog, released his own book.
YouTubers celebrate "vlogmas" in the run-up to Christmas, where the stars post videos every day during Advent.
Because of their break, it seems Alfie and Zoella won't complete the series of videos.
In a post previously shared on Twitter, Zoella said of the revelations about her novel: "Of course I was going to have help from Penguin's editorial team in telling my story.
"The story and characters of Girl Online are all mine."
Another writer, Siobhan Curham, who is thanked in the book's acknowledgements, has been responding to Twitter comments about the Girl Online revelations.
Zoella, whose real name is Zoe Sugg, is also thought to have recognised the author's contribution during promotion for the book.
Ms Curham has yet to respond to Newsbeat's request for a comment.
A spokesperson for Penguin said: "As publishers our role is, and always has been, to find the very best talent and help them tell their story and connect them with readers.
"Talented You Tube entrepreneurs such as Zoe are brilliant at understanding and entertaining their audience.
"For her first novel, Girl Online, Zoe has worked with an expert editorial team to help her bring to life her characters and experiences in a heart-warming and compelling story."
Penguin added: "We are proud to be have been able to help Zoe tell her story and that the book is proving so successful in getting young people reading."
Many of Zoella's fans sent positive messages to the YouTube star after her announcement, saying that they still "loved" the book.
More than 78,000 copies of Girl Online were sold in its first week of publication.
After the figures were released, Zoella, whose real name is Zoe Sugg, tweeted: "I'm legit blown away by this. I never in a million years thought that so many of you would pick up a copy of Girl Online. Almost want to cry."
The record is the highest since Nielsen BookScan began collecting information on the book market in 1998, according to The Bookseller.
It is the first of a two-book deal Zoella has with Penguin.
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The European Union (EU) has appealed against a recent World Trade Organization (WTO) ruling in favour of the US over its state aid for Boeing.
[NEXT_CONCEPT]
Zoella has temporarily quit the internet.