US 6593123

I'll search for information on this specific patent number, including any 2026 litigation activity.

Let me run one more targeted check for any litigation or CAFC activity specifically involving this patent.

Let me retrieve the actual claim set of US 6,593,123 B1 (the truncated text cuts off before the claims).

US Patent 6,593,123 B1 — Summary

⚠️ Search-scope note up front: I found no evidence of any CAFC (Federal Circuit) 2026 docket, appeal, IPR, or district-court action involving U.S. Patent 6,593,123 specifically. My searches of 2026 Federal Circuit summaries, PTAB/PTACTS petition records, and litigation coverage returned nothing naming this patent number. The AAV gene-therapy patent litigation that is active in 2024–2026 (Genzyme/Avigen successor v. Novartis over Zolgensma; Genzyme v. Sarepta over Elevidys) asserts different patents — e.g., U.S. 9,051,542; 7,704,721; 7,125,717; 7,846,729; 8,093,054; 7,785,888; 6,596,535; 12,013,326; 12,031,894. I cannot confirm any adjudication of '123. Treat the litigation statement as "nothing found," not as "confirmed inactive."

Bibliographic data (from the patent front page / Google Patents)

Identifier caveat (no auto-correction applied): the front-page inventor listing reads "Quang Qu," but the recorded assignment entries on Google Patents name the assignor as both "QU, QUANG" (2000-08-07 record) and "QU, GUANG" (2001-12-10 record). I am reporting both spellings as they literally appear rather than reconciling them. Also note both "Microfluidics International Corp." and "Pall Membrane Technology Corporation" and "Pall Corporation" appear as the cited vendor names — reported as written.

Family (related filings): PCT/US2001/018443 → WO 2002/012455 A1; AU 2001269757 A1; and U.S. 10/440,704 → US 2003/0207439 A1 (a continuation of 09/633,834, published with a different claim set — do not conflate the two documents' claims).

Abstract (verbatim, as printed)

"Methods are provided for large-scale purification of recombinant AAV (rAAV) virions that were produced in the absence of infectious adenovirus. Preferably, the rAAV is produced in a host cell line via triple-transfection with an accessory function vector, an AAV vector, and an AAV helper vector. The methods include preparing a lysate from the host cell line and passing that lysate over various combinations of ion exchange chromatography media and/or affinity chromatography media. The affinity chromatography medium is an AAV receptor or an antibody with binding affinity for AAV, e.g., heparin sulfate. A variety of cation exchange and anion exchange media are contemplated by the present invention. In certain embodiments, optional purification steps may be included, such as filtering the lysate through one or more filters, or treating the lysate with a nuclease."

Plain-language overview of the independent claims

The patent has three independent claims — claims 1, 12, and 20.

Claim 1 — Anion-exchange flow-through, then heparin/affinity capture, with a sarcosine wash.
A method of purifying rAAV from contaminants that strings together the production and the purification:

• (a)–(c) introduce an AAV vector into a host cell; introduce a first nucleic acid supplying AAV helper functions and a second nucleic acid supplying accessory functions, where the accessory nucleic acid and the host cell together lack a gene needed to make adenovirus (i.e., helper-virus-free production); then culture the cell to make rAAV;
• (d) prepare a lysate;
• (e)–(f) run the lysate over an anion exchange medium under conditions where the contaminants bind but rAAV flows through (flow-through mode), and collect that flow-through;
• (g)–(i) pass the flow-through over an affinity medium, wash with an anionic detergent comprising sarcosine, then elute purified rAAV.
  The sarcosine wash (as opposed to, e.g., urea or deoxycholate) is the distinguishing purification step — the specification reports it removed the most contaminating protein.

Claim 12 — Cation-exchange capture, then affinity capture, plus sarcosine wash.
Same purification goal, but starting from a simpler premise ("providing a host cell comprising rAAV virions," with no recitation of how it was made):

• (b)–(e) make a lysate, load it on a cation exchange medium so the rAAV binds (bind-elute mode rather than flow-through), wash, and collect the eluate;
• (f)–(i) pass the eluate over an affinity medium, wash with sarcosine-containing anionic detergent, and elute purified rAAV.

Claim 20 — Anion-exchange flow-through, then affinity capture (truncated in the available text).
Also a "purifying rAAV from contaminants" method, with steps including "(f) passing said eluate over an anion exchange chromatography medium, thereby binding said contaminants to said anion exchange chromatography medium" and "(g) passing the eluate obtained in step (f) over an affinity chromatography medium…".
Uncertainty: the full text of claim 20 (steps (a)–(e) and the closing steps) and claim 21 were cut off in the sources I could retrieve; I do not have authoritative wording for the complete claim 20 or for dependent claim 21, and I am not going to reconstruct them from the continuation's claim set, which differs.

Dependent claims — quick map

• Claim 2 / 3: order of the AEX vs. affinity steps (AEX-first or affinity-first).
• Claim 4 / 5 (and 18/19): affinity medium is an AAV-binding molecule — an AAV receptor or an anti-AAV antibody; preferably heparin sulfate.
• Claim 6: lysate made by microfluidization.
• Claim 7: further comprising filtering the lysate.
• Claim 8: host cells cultured substantially serum-free.
• Claim 9: treating the lysate with a nuclease (specification: BENZONASE™).
• Claim 10: host cell line cultured in a bioreactor.
• Claim 11: host cell line transfected with an accessory function vector, an AAV vector, and an AAV helper vector (triple transfection).
• Claims 13–17: step-order permutations for the claim 12 cation-exchange embodiment.
• Claim 14: cation exchange medium = sulfo-, phospho-, carboxy-, or carboxy-methyl-based resin.

Practical context

• Why it mattered: the patent's stated problem is that prior rAAV purification processes were built to remove infectious helper adenovirus and therefore required heat inactivation (≈50% titer loss). Because rAAV here is made without infectious helper virus, the process can be a shorter, scalable, column-only train (roller bottles / bioreactor → microfluidization → filtration → chromatography), with the specification reporting >80% overall rAAV recovery by Q-PCR across the exemplified AEX + heparin process.
• Cited prior art of record includes WO 96/27677, WO 97/08298, WO 99/11764, WO 99/61643, WO 00/22152, WO 00/23116, plus Ferrari et al. (Nature Medicine 1997), Xiao et al. (J. Virol. 1998), Qu et al. (ACS abstract 2000), Anderson et al. (2000), Grimm et al. (1998), and Clark et al. (1999).
• Downstream relevance: '123 is frequently cited as background art and expressly incorporated by reference in later AAV manufacturing/production patent families (e.g., EP 1,951,888; EP 2,781,596; EP 2,529,020; and recent WO/US applications on ion-exchange AAV purification) — so its main modern footprint is as cited literature, not as an asserted or adjudicated patent.

Bottom line on your two questions: (1) The bibliographic and claims summary above is well-grounded in the patent text itself. (2) As for "USPTO database and CAFC 2026 dockets for 6,593,123" — I found no 2026 CAFC docket or pending litigation on this patent, and given its recorded expiration on 2020-08-07, any such proceeding would be unusual. I cannot rule out a filing that isn't indexed in the sources I could reach, so please verify against PACER/CAFC docket search directly if that detail is load-bearing.