Fastcase, vLex and Clio: One Family, Which APIs Exist?

Short answer: Fastcase and vLex merged in 2023, and Clio said on November 10, 2025 that it had completed its purchase of vLex, so all three names now sit in one company family. Fastcase sells a legal data API and data feeds through its sales team and publishes no documentation for them. vLex runs a developer portal where you can sign up for keys, but its public pages do not show which APIs are open today. Docket Alarm, a court-docket product in the family, is the one we found with a public API specification. Clio's own developer documentation covers practice management, and we found no research API in it.

TL;DR

• The corporate story is simple and dated. Fastcase and vLex announced a merger on April 4, 2023. Clio signed an agreement to buy vLex on June 30, 2025 and announced completion on November 10, 2025.
• Fastcase's API is a sales conversation. The company's page says to contact sales. It lists no documentation, no price and no terms for the API.
• vLex has a developer portal. It invites you to sign up for keys. The vLex terms say API use must be included in your subscription agreement.
• We found no public API for Vincent, the vLex AI assistant, or for the research libraries themselves.
• One product in the family is openly documented. The Docket Alarm API covers court dockets and filings.
• Clio's developer docs cover running a law firm, such as matters, contacts and billing. We found no research API in them.

Where each name came from

The 2023 and 2025 deals make more sense once you know where each company started. Three different origin stories ended up in one family.

vLex says on its about page that "In 2000, Lluis and Angel Faus founded vLex in Barcelona with a vision to make legal knowledge more accessible through technology."

Fastcase came from two lawyers who left a big firm. LawSites, the legal technology blog by journalist Bob Ambrogi, reported in January 2021 that Ed Walters and Phil Rosenthal "were associates at Covington & Burling when they left the firm to found Fastcase in 1999." Its reach grew through bar associations. A bar association is the professional body a lawyer joins to practise in a state, and many of them buy a research subscription on behalf of every member.

The same article covers the next chapter. In January 2021, Fastcase merged with its longtime rival Casemaker, which had started in the late 1990s when a Cincinnati attorney teamed up with the Ohio State Bar Association to build a searchable database of Ohio cases. LawSites reported that the combined subscriber base included bar associations in all 50 states and reached more than 1 million of the country's estimated 1.3 million lawyers. "Starting today," Fastcase cofounder and CEO Ed Walters said, "every member of a state bar in the country has access to legal research through our blended company."

Keep that picture in mind when you read the vLex terms below. A bar-association benefit is a subscription for people who read and search. A licence that lets software pull the data is a separate agreement.

Docket Alarm was a separate company until Fastcase's press release of January 10, 2018 announced its purchase. The release describes Fastcase's "expansion into the federal and state docket alerts, legal news and data analytics markets" and says Docket Alarm was founded by intellectual property litigator Michael Sander. A docket is the running list of filings in a court case, which is why it counts as a different kind of data from the opinions a judge writes.

Clio says its own history page starts in 2008, when Jack Newton and Rian Gauvreau founded it, and that it launched its annual Clio Cloud Conference in 2013. The two product lines were also neighbours long before the vLex deal. When Clio announced new integration partners on October 22, 2019, LawSites' list included Fastcase BK, a bankruptcy forms tool that saves documents to the right matter in Clio. So a Fastcase product was already listed as a Clio integration six years before the vLex deal.

What is announced and what has happened

It helps to separate three things: what a company said it would do, what it said it did, and what we can see on its websites today. Every date in this section comes from the companies' own pages, which we read on October 5, 2026.

April 4, 2023: Fastcase and vLex merge. Fastcase's own announcement says the two companies were "merging to form the world's largest law firm subscriber base with more than one billion legal documents from more than 100 countries." The combined business was to be called vLex Group, and its products would "retain the name of vLex in global markets and Fastcase in the U.S." Oakley Capital and Bain Capital Credit invested in the combined business.

June 30, 2025: Clio signs a deal for vLex. Clio's announcement, republished on the vLex site, says Clio "signed a definitive agreement to acquire vLex" in a transaction "valued at US $1 billion" and paid in cash and stock. It said the deal was "expected to close later this year, subject to customary closing conditions and regulatory approvals." At this point the purchase had not closed.

November 10, 2025: Clio says the deal closed. Clio's site blocks automated readers, so we read its release as republished by investor JMI Equity. It says Clio "today announced it has completed its US$1 billion acquisition of vLex." It describes the combined offer as an "Intelligent Legal Work Platform" that unites Clio's practice software with vLex's Vincent AI.

What Clio said about products and brands. The two releases and Clio's announcement blog post talk about Vincent and the platform. None of them says whether the Fastcase or vLex names will continue. What we can see today is a mix. The Fastcase home page carries a banner that reads "Fastcase is now part of Clio." The vLex site lists Vincent, vLex Library and Fastcase Library as separate products. The Clio App Directory page at the address ending in /fastcase is titled "Clio Library." We record that as an observation, and we found no announcement of a rename. If a contract matters to you, ask which legal entity and which product name will appear on it.

Which APIs exist, in one table

A "publicly documented" API here means you can read what it does without a sales call. "No documentation found" means we searched the product pages, the developer portal, the knowledge base index and the terms. It does not prove that no private API exists.

What each company says about its API

Fastcase. The Legal Data API page says you can "receive specialized legal data feeds and APIs directly from Fastcase & Docket Alarm," and that feeds can arrive in formats such as JSON and XML. It offers bulk access and delivery to third-party dashboards. The page ends with a contact form and gives no price, rate limit or terms. An older Fastcase blog post says the same thing and adds that its data API "allows your system to query ours" and that you should contact sales for a demo.

vLex. The vLex developer portal describes its purpose as a place to "discover APIs, learn how to use them, try them out interactively, and sign up to acquire keys." The home page lists an anonymisation API you can try, and labels two others, including Vincent, as upcoming. The page carries a 2020 copyright line, so it may be out of date. We could not confirm from public pages which APIs are open for new users.

The vLex terms are more direct. They forbid automated access, including robots and data mining tools, "except as explicitly authorized by us in writing or through a separate agreement (such as API licenses)." They also say API use "is permitted only if the API service is explicitly included in the Subscription Agreement." In plain terms: a normal research subscription does not let you point a script at the site.

Docket Alarm. This vLex product has a public API page that describes a "single unified REST API to hundreds of US courts," with login, search and docket retrieval calls. It covers court dockets and the filings attached to them. The page does not describe statutes or regulations.

Clio. Clio's developer documentation has API references for Clio Manage, Clio Grow and Clio Accounting. Those cover firm data such as matters, contacts and bills. The documentation we read has no reference for a research library or for Vincent. Our guide to the Clio API walks through what is there.

What to check before you choose

Work through these questions in order. They take you from your need to a contract.

1. What do you need back? Court dockets point to the Docket Alarm API. Case law, statutes and regulations as raw data point to the Fastcase feeds. AI answers point to Vincent, where you should ask what programmatic access exists.
2. Who will see the output? Your own staff reading research is one thing. Showing the text to your customers inside a product is another, and it needs a licence that allows redistribution. Ask for that in writing.
3. Is the API in your agreement? The vLex terms tie API use to the subscription agreement. A bar-member benefit is a research subscription. We found nothing that says it includes an API.
4. Which company signs, and under which name? After an acquisition, contracts and product names can change. Ask what happens to your terms if the product is renamed or merged.
5. What are the practical limits? Ask for update frequency, rate limits, response formats, support hours and price, in writing. Our ten questions for a legal data vendor turns this into a checklist.
6. Is licensing the right route for this data? Our build or buy guide lays out the choices.

If what you need is US statutes, regulations, court rules and agency guidance retrieved by citation, a primary-law API such as Vaquill AI publishes its endpoint list openly. See the US law data guide for how the options compare. For a price-focused view of the research products themselves, see our posts on Fastcase versus Lexis and Westlaw versus vLex.

FAQ

Did Clio buy Fastcase?

Indirectly. Fastcase and vLex merged in April 2023 to form vLex Group. Clio signed an agreement to buy vLex on June 30, 2025 and announced on November 10, 2025 that the purchase was complete. The Fastcase website now says "Fastcase is now part of Clio."

Does Fastcase have a public API?

Fastcase offers a legal data API and data feeds, but its page does not publish documentation, pricing or terms. It tells interested companies to contact its sales team. Treat it as a contract product.

Does vLex have an API?

vLex has a developer portal at developer.vlex.com where visitors can sign up for keys. Its home page looks dated, and we could not confirm which APIs are open today. The vLex terms say API use must be explicitly included in your subscription agreement, so ask vLex directly.

Does Vincent have an API?

We found no public API documentation for Vincent. The vLex developer portal labels Vincent as upcoming, but the page may be old. If you need programmatic access to Vincent, ask the company what is available under contract.

Is there a Clio API for legal research?

Clio's published API references cover practice management in Clio Manage, Clio Grow and Clio Accounting. We found no research API in them. Clio's help center says Vincent can read matter context from Clio Manage inside Clio's own products, which is a different thing from a public API. Our Clio API guide explains where research data can fit.

Does my bar's free Fastcase access include API access?

We found nothing that says so. Bar associations offer the research product as a member benefit, and the vLex terms say API use is allowed only when the subscription agreement includes it. Check your bar's terms or ask the vendor.

Can I scrape vLex or Fastcase for data?

The vLex terms forbid automated access, including robots and data mining tools, unless vLex authorizes it in writing or through an agreement such as an API licence. If you need data in bulk, ask for a feed or an API licence.

For readers who want US primary law behind an API with published endpoints, see /legal-api.

Priyansh Khodiyar

Co-Founder & CTO

Priyansh leads engineering and AI at Vaquill AI: the pipelines that pull statutes, regulations and court rules from every US jurisdiction's official publisher, and the REST API, MCP server and open dataset that serve them.