Continuous Fiber 3D Printing (CF3D) technology developer Continuous Composites, Inc. (CCI) has filed a patent infringement lawsuit against three entities associated with the FibreSeek and Anisoprint brands.
Filed on August 7, 2026 in the US District Court for the District of Delaware, the complaint alleges infringement of ten US patents covering continuous fiber additive manufacturing.
The 40-page filing, accompanied by a jury demand, names Anisoprint S.A.R.L., Anisoprint 3D Printing Technology (Suzhou) Limited, and Shenzhen Fibreseek Technology Co., Ltd. as defendants. The case has been assigned to Judge Maryellen Noreika under docket number 1:26-cv-01002. Kelly E. Farnan of Richards, Layton & Finger, PA is listed as Delaware counsel of record for CCI.
“This lawsuit is not about a single patent or isolated feature,” said Steve Starner, CEO of Continuous Composites. “The complaint alleges infringement across ten separate U.S. patents covering core technologies that helped establish continuous fiber additive manufacturing as a viable manufacturing process.”
CCI alleges in its complaint that FibreSeek’s products, including the recently launched FibreSeeker 3 continuous fiber 3D printer, use a continuous fiber co-extrusion approach that falls within the scope of its patents.
The Patent Family Behind The Case
The ten patents asserted in the complaint are US 9,511,543; 10,603,836; 10,744,708; 10,759,109; 11,173,660; 11,577,455; 11,584,069; 11,590,699; 12,257,772; and 12,403,651. All ten share the same title, “Method and apparatus for continuous composite three-dimensional printing,” and name the same sole inventor, Kenneth Lyle Tyler, co-founder of CCI.
The ten asserted patents form a related US patent family. They claim priority through US application 13/975,300, filed on August 24, 2013, which itself claimed priority to a provisional application filed on August 29, 2012. US 13/975,300 subsequently issued as US 9,511,543 in December 2016.
They share a common title and much of the same technical disclosure, but contain different claim sets addressing different method and apparatus features. The scope of each patent is determined by its individual claims. Whether the FibreSeeker 3 satisfies every requirement of any asserted claim is disputed and has not been determined by the court.
The shared specification describes embodiments in which two or more materials are incorporated into a composite during deposition, including a solid continuous strand combined with a matrix material.
CCI describes the 2012 filing as the ‘industry’s earliest patent application’ directed at continuous-fiber additive manufacturing. 3D Printing Industry has not independently established that priority claim.
The family spans filings from 2012 to November 2023, with the two most recent patents (US 12,257,772 and US 12,403,651) granted in March and September 2025. According to CCI, licensing discussions with FibreSeek continued through 2024 and 2025.
Several patents in the family were previously challenged during the Continuous Composites lawsuit against Markforged. Markforged filed seven inter partes review (IPR) petitions concerning five CCI patents. The US Patent Trial and Appeal Board (PTAB) declined to institute review in six proceedings.
In the seventh, involving US 10,744,708, the Board instituted review but ultimately held that Markforged had not proved claims 1-14 unpatentable on the grounds presented. That decision concerned those particular claims and challenges; it was not a ruling on the validity of the entire patent family.
The district-court proceedings produced a more mixed record. Four patents originally asserted against Markforged were removed from the case in April 2023. At trial in April 2024, the jury considered two claims from US 11,173,660. It found one claim invalid and not infringed, but found the other infringed and awarded CCI $17.34 million.
The parties subsequently entered a settlement and patent-license agreement requiring payments totaling $25 million. The agreement also included cross-licenses, mutual releases and covenants not to sue, and stated that neither party admitted liability or wrongdoing.
As previously reported by 3D Printing Industry in February 2025, CCI is also involved in a separate legal dispute with former counsel Lee & Hayes over fees arising from the Markforged litigation. The law firm has claimed it is owed a $7.2 million contingency fee, while CCI has argued that Lee & Hayes agreed to accept $3 million.
In May 2026, the Spokane Journal of Business reported that a federal judge had ruled that CCI breached its contingency-fee agreement with Lee & Hayes, rejecting CCI’s argument that the fee had been reduced to $3 million. The litigation subsequently moved to the damages phase to determine the amount owed. CCI said it disagreed with the ruling and intended to appeal.
CCI Says Licensing Discussions Began in 2023
According to the complaint, CCI first approached FibreSeek about a possible licence in 2023. In June 2024, CCI says it provided proposed licensing terms. Additional discussions continued through 2024 and 2025 but did not produce an agreement, according to CCI.
In an open letter to the AM community published alongside the lawsuit announcement, CEO Steve Starner wrote that the company “proposed licensing frameworks” and “made repeated efforts to reach a mutually acceptable resolution” before filing suit.
CCI asks the court for monetary relief and injunctive relief against conduct ultimately found to infringe the asserted patents. As of August 18, 2026, no defendant had filed a substantive response.
According to CCI, it holds more than 120 allowed US patents and more than 40 international patents. CCI has previously enforced patents from the same family against Markforged, but the outcome of that litigation does not determine the present dispute. The new case will depend on the construction and validity of the particular claims asserted, the operation of the accused FibreSeek products, and the evidence presented by the parties.
At this stage, CCI’s allegations have not been tested. The case could provide further guidance on how claims from CCI’s continuous-fiber patent portfolio apply to competing commercial extrusion systems.
3D Printing Industry sent detailed questions concerning CCI’s infringement allegations, the asserted patents, the licensing discussions described in the complaint, and the relationships between the named defendants. Anisoprint S.A.R.L., Anisoprint 3D Printing Technology (Suzhou) Limited and Shenzhen Fibreseek Technology Co., Ltd. were given an opportunity to respond before publication. No substantive response to the questions or the infringement allegations had been received at the time of publication.
3D Printing Industry is inviting speakers for its 2026 Additive Manufacturing Applications (AMA) series, covering Energy, Healthcare, Automotive and Mobility, Aerospace, Space and Defense, and Software. Each online event focuses on real production deployments, qualification, and supply chain integration. Practitioners interested in contributing can complete the call for speakers form here.
To stay up to date with the latest 3D printing news, don’t forget to subscribe to the 3D Printing Industry newsletter or follow us on LinkedIn.
Explore the full Future of 3D Printing and Executive Survey series from 3D Printing Industry, featuring perspectives from CEOs, engineers, and industry leaders on the industrialization of additive manufacturing, 3D printing industry trends 2026, qualification, supply chains, and additive manufacturing industry analysis.
Featured image shows Continuous Composites’ CF3D printing technology. Photo via Continuous Composites.
