patentsview

PatentsView / USPTO Patent Search Skill

Searches U.S. patent data for technology relevant to direct lithium extraction (DLE), produced water treatment, membrane separation, and critical mineral recovery.

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Credential

None required. The USPTO Open Data Portal is publicly accessible.

# No API key needed -- USPTO patent data is public domain

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Data Source

Field	Value
Primary source	USPTO Open Data Portal (ODP)
Portal URL	https://data.uspto.gov/
Legacy system	PatentsView (patentsview.org) -- migrated to ODP
Coverage	All U.S. patents and published applications (1790-present)
Update frequency	Weekly (Tuesday patent grants, Thursday applications)
Formats	Web search, bulk data downloads (CSV, JSON)

Important migration note (as of 2025): PatentsView has migrated to the USPTO Open Data Portal at https://data.uspto.gov/. The legacy PatentsView API at search.patentsview.org/api/v1/ and api.patentsview.org returns {"error":true, "message":"PatentsView is migrating to the USPTO Open Data Portal"}. Use the ODP web interface or bulk data downloads instead.

Transition guidance: https://data.uspto.gov/support/transition-guidance/patentsview

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Access Patterns

USPTO Open Data Portal (Primary)

The ODP at https://data.uspto.gov/ provides a web-based search interface. As of the migration, programmatic API access should be verified through the ODP documentation. The portal supports:

• Full-text search across patent titles, abstracts, and claims
• Filtering by CPC/USPC classification, date range, assignee, inventor
• Export of search results

USPTO Full-Text Search (PatFT / AppFT)

The traditional USPTO full-text search remains available:

# Search granted patents (PatFT) -- returns HTML, not JSON
# Use for keyword + classification queries
curl -s "https://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO2&Sect2=HITOFF&u=%2Fnetahtml%2FPTO%2Fsearch-adv.htm&r=0&p=1&f=S&l=50&Query=TTL%2Flithium+AND+ABST%2Fbrine+AND+ISD%2F1%2F1%2F2020-%3E&d=PTXT"

USPTO Bulk Data (Programmatic Access)

For patent landscaping, the bulk data downloads are the most reliable programmatic option:

# USPTO bulk data catalog
# https://bulkdata.uspto.gov/
# Weekly XML files of patent grants and applications

# PatentsView bulk data (research datasets, still hosted)
# https://patentsview.org/download/data-download-tables
# Pre-processed CSV/TSV tables: patents, claims, CPC, assignees, inventors

Google Patents (Supplementary)

Google Patents provides a free searchable interface with CPC classification:

https://patents.google.com/?q=lithium+extraction+brine&oq=lithium+extraction+brine

Lens.org (Supplementary, API Available)

Lens.org provides a patent search API with free academic access:

# Lens.org API (requires free API key for academic use)
curl -s "https://api.lens.org/patent/search" \
  -H "Authorization: Bearer $LENS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "query": {"bool": {"must": [
      {"match": {"abstract": "lithium extraction brine"}}
    ]}},
    "size": 10,
    "sort": [{"date_published": "desc"}]
  }'

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Key CPC Classifications for DLE Research

CPC Class	Description	Relevance
C22B26/12	Obtaining lithium	Core DLE technology patents
C01D15/00	Lithium compounds	Lithium carbonate/hydroxide production
C22B3/00	Extraction of metals by wet processes	Hydrometallurgy (includes brine)
C22B3/04	By leaching	Acid/base leaching of ores and brines
B01D61/00	Processes using semipermeable membranes	Membrane separation (NF, RO, ED)
B01D61/42	Electrodialysis	ED for brine concentration
B01J20/00	Solid sorbent compositions	Ion exchange / adsorption sorbents
B01J39/00	Cation exchangers	Lithium-selective ion exchange
C02F1/00	Treatment of water / wastewater	Produced water treatment
C02F1/469	Electrochemical treatment	Electrochemical Li recovery
C25C1/02	Electrolysis - alkali metals	Electrolytic lithium production
E21B43/00	Methods for obtaining oil/gas/water	Well production methods

CPC Query Syntax for USPTO Search

# PatFT advanced search syntax:
# CPC/C22B26/12    -- lithium recovery
# CPC/C01D15$      -- lithium compounds ($ = all subclasses)
# CPC/B01D61$      -- membrane processes
# Combine: CPC/C22B26/12 AND ABST/brine

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Workflow

Step 1 -- Resolve Intent

User asks about...	Search strategy
DLE technology patents	CPC C22B26/12 + keywords "brine" "extraction"
Sorbent / adsorbent patents	CPC B01J20 or B01J39 + "lithium" "selective"
Membrane separation patents	CPC B01D61 + "lithium" "brine" "produced water"
Electrochemical Li recovery	CPC C02F1/469 or C25C1/02 + "lithium"
Specific company patents	Assignee name + lithium/DLE keywords
Recent patents only	Add date filter ISD/1/1/2023->
Patent landscape overview	Broad CPC search + count by assignee/year

Step 2 -- Search Patents

Option A: USPTO ODP web search (recommended for interactive use):

Direct the user to https://data.uspto.gov/ with a pre-formed query.

Option B: Google Patents programmatic (for quick results):

# Google Patents search URL (opens in browser, not a REST API)
# Useful for generating a search link for the user
echo "https://patents.google.com/?q=(lithium+extraction+brine+produced+water)&oq=lithium+extraction+brine&type=PATENT&status=GRANT&country=US&after=priority:20200101"

Option C: PatentsView bulk data analysis (for patent landscaping):

# Download PatentsView CPC classification table
curl -L -o /tmp/g_cpc_current.tsv.zip \
  "https://s3.amazonaws.com/data.patentsview.org/download/g_cpc_current.tsv.zip"

# After unzipping, filter for lithium CPC classes
zcat /tmp/g_cpc_current.tsv.zip | head -1
# patent_id  cpc_section  cpc_class  cpc_subclass  cpc_group  cpc_subgroup  cpc_category  cpc_sequence

# Count patents in lithium recovery class
zcat /tmp/g_cpc_current.tsv.zip | awk -F'\t' '$5=="C22B26" && $6~/12/' | wc -l

Step 3 -- Parse and Analyze

For patent landscaping, compute:

• Patent count by year (filing date and grant date)
• Top assignees by patent count
• CPC co-classification patterns (what other tech areas appear?)
• Geographic distribution of inventors

Step 4 -- Produce Output

Format: Patent Results Table + Landscape Summary

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Output Format

Example 1: Patent Search Results

## U.S. Patents: Direct Lithium Extraction from Brines (CPC C22B26/12)

**Search:** CPC C22B26/12 AND abstract contains "brine"
**Total results:** ~340 granted patents
**Showing:** 10 most recent

| Patent No. | Title | Grant Date | Assignee | Key CPC |
|------------|-------|------------|----------|---------|
| US 11,834,xxx | Method for selective lithium extraction using ... | 2023-12-05 | Lilac Solutions | C22B26/12 |
| US 11,802,xxx | Electrochemical lithium recovery from ... | 2023-10-31 | EnergyX | C22B26/12, C25C1/02 |
| ... | ... | ... | ... | ... |

**Landscape Summary:** DLE patent filings have accelerated sharply since 2018,
with ~120 of 340 total patents filed in 2020-2023. Top assignees include Lilac
Solutions (18 patents), Standard Lithium (12), EnergyX (9), and Schlumberger/SLB
(8). Technology focus areas: lithium manganese oxide sorbents (35%), lithium
titanate sorbents (15%), membrane-based separation (20%), and electrochemical
methods (15%). The remaining 15% cover solvent extraction and hybrid approaches.

Example 2: Technology-Specific Search

## Patent Search: Lithium-Selective Ion Exchange Sorbents

**Search:** CPC B01J39 AND "lithium" AND "manganese oxide"
**Results:** ~85 granted patents

| Patent No. | Title | Filing Date | Assignee |
|------------|-------|-------------|----------|
| ... | ... | ... | ... |

**Key finding:** Lithium manganese oxide (LMO) sorbent patents dominate the
selective extraction space. Most patents claim specific Mn:Li ratios, dopants
(Al, Fe, Ti), and granulation methods. Freedom-to-operate analysis should
focus on the specific sorbent composition and regeneration chemistry.

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Error Handling

Issue	Cause	Action
PatentsView API returns migration error	API deprecated, moved to ODP	Use USPTO ODP web search, Google Patents, or bulk data
USPTO bulk data download fails	Large file size (GB+)	Download specific tables only (CPC, patent, assignee)
Too many results	Broad query	Add CPC class filter or date range
Zero results	Overly narrow query	Remove date filter; broaden keywords; check CPC class
CPC class not found	Incorrect class notation	Verify at https://www.cooperativepatentclassification.org/
Google Patents rate limiting	Too many automated requests	Space requests; use bulk data for large analyses

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Caveats

1. PatentsView API is deprecated. As of 2025, PatentsView has migrated to the USPTO Open Data Portal (data.uspto.gov). The legacy API endpoints return error messages. Use the ODP web interface, bulk data downloads, or supplementary sources (Google Patents, Lens.org).

2. Patent does not equal commercial product. Many DLE patents describe lab-scale processes that have not been commercialized. Patent claims may be broader than actual demonstrated capability.

3. International coverage. This skill focuses on U.S. patents (USPTO). Major DLE patent activity also exists in China (CNIPA), Australia (IP Australia), and via PCT (WIPO). For international coverage, use Lens.org or Google Patents (which indexes multiple jurisdictions).

4. Patent classification lag. CPC codes are assigned during examination and may take 12-18 months after filing to appear. Very recent applications may not have full CPC assignments.

5. Published applications vs. granted patents. Patent applications (published 18 months after filing) represent claimed inventions that may not be granted. Distinguish between published applications and granted patents in landscape analysis.

6. Freedom-to-operate is not patent search. Finding patents in a technology area does not constitute a freedom-to-operate analysis. FTO requires claim-by-claim analysis by a patent attorney. This skill provides landscape awareness, not legal advice.

7. Bulk data size. PatentsView bulk data tables can be multiple GB. Download only the specific tables needed (CPC, patent, assignee) rather than the full dataset.

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Implementation Notes

• Primary access is now through the USPTO ODP web interface or bulk data
• For interactive searches, generate a search URL and present to the user
• For patent landscaping, download PatentsView bulk CSV/TSV tables and analyze locally
• Use jq, awk, or Python for bulk data filtering
• CPC classification browser: https://www.cooperativepatentclassification.org/
• For academic research, Lens.org (https://www.lens.org/) offers a free API with registration
• Combine patent data with pnge-core:pnge-literature for citing literature analysis