Prior art

To find the most relevant prior art for US patent 12305206, I will search the USPTO Patent Public Search tool for the patent and examine its cited references. "Prior art" refers to information publicly known before a patent's effective filing date.

The USPTO Patent Public Search tool allows searching by patent number. Utility patents, such as US12305206, typically have six to eight digits.

Based on my analysis of US12305206B2, here are some of the most relevant prior art citations mentioned within the patent itself. Since the task specifically asks for a search of the USPTO database for prior art, I will list the patents explicitly cited in the "Description of the Related Art" or "Background" sections, as these are considered by the patent examiners during the application process and represent documents the applicant deemed relevant.

Here's an analysis of the prior art explicitly referenced in US12305206B2:

1. U.S. Pat. No. 8,227,228

• Full Citation: U.S. Pat. No. 8,227,228 B2
• Publication/Filing Date: The patent itself states, "U.S. Pat. No. 8,227,228 describes DAAO enzymes from Candida intermedia." To get the precise filing and publication dates, a direct search of this patent would be needed.
• Brief Description: This patent describes DAAO enzymes from Candida intermedia. The enzymes can be modified for increased activity and used in methods like those described in US12305206.
• Potentially Anticipating Claims (35 U.S.C. § 102): This patent potentially anticipates claims related to the use of DAAO enzymes for the conversion of D-glufosinate to PPO, particularly if the DAAO enzyme is derived from Candida intermedia or if the claims broadly cover the use of DAAO enzymes without specifying the required high activity or specific mutations. Claims 1-13, related to the method of making L-glufosinate using a DAAO enzyme, could be relevant.

2. U.S. Pat. No. 7,939,709

• Full Citation: U.S. Pat. No. 7,939,709 B2
• Publication/Filing Date: The patent states, "See, U.S. Pat. No. 7,939,709, which is incorporated herein by reference." A direct search would provide the exact dates.
• Brief Description: This patent is referenced in relation to mutations at position 56 of the DAAO enzyme, specifically suggesting that "the wild type threonine can be replaced by Ala, Cys, Gly, Ile, Asn, Arg, Ser, Thr, Met, or Val."
• Potentially Anticipating Claims (35 U.S.C. § 102): Claims describing mutant DAAO enzymes with specific mutations, particularly at position 56, could be anticipated. For example, claims that specify the T56M mutation in the DAAO enzyme, or broader claims covering mutations at position 56, might be affected.

3. U.S. Pat. No. 5,162,212

• Full Citation: U.S. Pat. No. 5,162,212
• Publication/Filing Date: The patent states, "In particular, see, for example, EP0249188, and U.S. Pat. No. 5,162,212, incorporated herein by reference."
• Brief Description: This patent is cited in the context of TA enzymes from various microorganisms, including Streptomyces hygroscopicus, Streptomyces viridochromogenes, and Candida albicans, for use in converting PPO to L-glufosinate.
• Potentially Anticipating Claims (35 U.S.C. § 102): Claims related to the use of transaminase enzymes from these or similar microorganisms for the amination step (conversion of PPO to L-glufosinate) could be anticipated. This might affect claims 1-13, particularly those specifying the type of TA enzyme used.

4. U.S. Pat. No. 7,723,576

• Full Citation: U.S. Pat. No. 7,723,576 B2
• Publication/Filing Date: This patent is mentioned in the context of "Hawkes reaction set forth in U.S. Pat. Nos. 7,723,576; 7,939,709; 8,642,836; and 8,946,507".
• Brief Description: These Hawkes patents describe DAAO reactions. US12305206B2 specifically contrasts its oxygen introduction method with these patents, noting that the Hawkes reaction was conducted in a sealed vessel, implying a difference in oxygen supply during the DAAO reaction.
• Potentially Anticipating Claims (35 U.S.C. § 102): This patent, along with the other Hawkes patents, could anticipate general claims related to the use of DAAO enzymes for D-glufosinate conversion, especially if claims do not sufficiently distinguish the oxygen supply method.

5. U.S. Pat. No. 8,642,836

• Full Citation: U.S. Pat. No. 8,642,836 B2
• Publication/Filing Date: This is another of the "Hawkes reaction" patents.
• Brief Description: Similar to US 7,723,576, this patent describes DAAO reactions, which US12305206B2 distinguishes based on oxygen introduction.
• Potentially Anticipating Claims (35 U.S.C. § 102): As with US 7,723,576, general claims involving DAAO-catalyzed conversion of D-glufosinate, without specific limitations on oxygenation, could be anticipated.

6. U.S. Pat. No. 8,946,507

• Full Citation: U.S. Pat. No. 8,946,507 B2
• Publication/Filing Date: This is the third of the "Hawkes reaction" patents mentioned.
• Brief Description: Also related to DAAO reactions, and distinguished by US12305206B2 based on oxygen introduction.
• Potentially Anticipating Claims (35 U.S.C. § 102): Similar to the other Hawkes patents, general claims regarding DAAO-catalyzed D-glufosinate conversion could be anticipated if not sufficiently distinguished by the method of oxygen delivery.

7. U.S. Pat. No. 9,255,115 B2

• Full Citation: U.S. Pat. No. 9,255,115 B2
• Publication/Filing Date: The patent mentions that "U.S. Pat. No. 9,255,115 B2 describes how the hydrochloric acid salt of L-glufosinate can be converted to the zwitterionic form with a base such as sodium hydroxide or sodium methoxide and then crystallized from aqueous alcohol solvent to afford L-glufosinate in relatively high purity."
• Brief Description: This patent details a method for purifying L-glufosinate by converting its hydrochloric acid salt to the zwitterionic form and crystallizing it.
• Potentially Anticipating Claims (35 U.S.C. § 102): This patent could potentially anticipate claims related to the purification and isolation of L-glufosinate, particularly those describing the conversion to a zwitterionic form and crystallization. Claims regarding the final purity and form of L-glufosinate in the compositions or formulations might be relevant.

Regarding the search for US Patent 12305206 on the USPTO database:

A direct search for "patent 12305206" on the USPTO Patent Public Search or Patent Center (which is the newer tool) would provide the official record, including a list of "Cited References" or "Prior Art" considered by the examiner. However, the question asks me to identify the most relevant prior art for US patent 12305206 and for each reference provide the full citation, publication/filing date, brief description, and which claim(s) it potentially anticipates under 35 U.S.C. § 102. Given the patent text provided, I have extracted the explicitly cited US patents as those would be considered the most relevant prior art by the applicant and examiner.

To fulfill the request of "Search the USPTO database for the specific patent number 12305206," a direct search on Patent Public Search or Patent Center would be performed. Since I cannot directly interact with a live database to extract this information, I am relying on the provided full patent text which lists its own prior art references. The current time in Washington D.C. where the USPTO is located is 02:47 AM, Friday, May 29, 2026.

It's important to note that the patent document US12305206B2 itself already contains the results of prior art searches conducted during its examination, and these listed US patents are those the applicant and examiner deemed most pertinent.