US 12305206

Here's a concise summary of US Patent 12305206B2, based on the provided text and information from the authoritative Google Patents link:

US Patent 12305206B2 Summary

• Title: Methods for making L-glufosinate
• Assignee: BASF SE
• Inventors: Brian Michael Green, Michelle Lorraine Gradley
• Filing Date: February 7, 2024 (Application number US18/435,340)
• Issue Date: May 20, 2025
• Abstract: The patent describes methods for producing L-glufosinate, also known as phosphinothricin or (S)-2-amino-4-(hydroxy(methyl)phosphonoyl)butanoic acid. The methods involve a two-step process: first, the oxidative deamination of D-glufosinate to PPO (2-oxo-4-(hydroxy(methyl)phosphinoyl)butyric acid), and second, the specific amination of PPO to L-glufosinate using an amine group from one or more amine donors. This combined approach significantly increases the proportion of L-glufosinate in a mixture of L-glufosinate and D-glufosinate.

Legal Status and Litigation:
The patent is currently active. The patent family is involved in litigation, with the first worldwide family litigation having been filed [cite: https://patents.darts-ip.com/?family=[58267184](/patent/58267184)&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=[US12305206](/patent/US12305206)(B2)]. Additionally, a PTAB case, PGR2026-00026, was filed and is currently pending [cite: https://portal.unifiedpatents.com/ptab/case/PGR2026-00026].

Plain-Language Overview of Independent Claims:

The provided patent text does not contain formally numbered claims. To provide an authoritative overview, I have retrieved the claims from the cited Google Patents link [cite: https://patents.google.com/patent/US12305206/en].

The independent claims of US12305206 are as follows:

• Independent Claim 1: This claim describes a method for producing L-glufosinate. It involves two main steps:

  1. Reacting D-glufosinate with a D-amino acid oxidase (DAAO) enzyme to create PPO (2-oxo-4-(hydroxy(methyl)phosphinoyl)butyric acid). The DAAO enzyme must have an activity of at least 3 µmol/min*mg, and the D-glufosinate is initially present in a racemic mixture of D- and L-glufosinate.
  2. Aminating the PPO to L-glufosinate using a transaminase (TA) enzyme and one or more amine donors.
     The method requires that either at least 70% of the D-glufosinate is removed, or the yield of L-glufosinate is at least 85% based on the input racemic glufosinate, or between 70% and 85% of the D-glufosinate is converted to L-glufosinate. [cite: https://patents.google.com/patent/US12305206/en]

• Independent Claim 13: This claim describes a composition for L-glufosinate. The composition contains a mixture of D-glufosinate, PPO, and L-glufosinate. In this mixture, L-glufosinate makes up at least 80% of the total weight of L-glufosinate, PPO, and D-glufosinate combined. [cite: https://patents.google.com/patent/US12305206/en]

• Independent Claim 14: This claim outlines a specific formulation. It comprises L-glufosinate ammonium at 10-30% by weight, and water as the balance. It also includes at least one of the following components:

  • Sodium alkyl ether sulfate (10-40% by weight)
  • 1-methoxy-2-propanol (0.5-2% by weight)
  • Dipropylene glycol (4-18% by weight)
  • Alkyl polysaccharide (4-20% by weight)
    [cite: https://patents.google.com/patent/US12305206/en]

• Independent Claim 19: This claim describes a method for controlling weeds in an area. The method involves applying an effective amount of a composition to the area. This composition contains L-glufosinate with an enantiomeric excess of greater than 90% over D-glufosinate. The area may contain glufosinate-resistant crops or planted seeds. [cite: https://patents.google.com/patent/US12305206/en]

• Independent Claim 20: This claim describes another method for controlling weeds, controlling weeds in non-field areas, defoliating plants or crops, or desiccating crops before harvest. The method involves applying an effective amount of a composition to the area. This composition contains L-glufosinate with an enantiomeric excess greater than 90% over D-glufosinate, and also includes PPO in an amount greater than 0.01% but less than 15%. [cite: https://patents.google.com/patent/US12305206/en]