The day before a veteran academic extension shut down, a small London team listed one under its name: what they inherited with 30k users was the name, not the product
What it is A Chrome extension that finds legal, free PDFs of papers with one click, using the name of Open Access Button, a veteran academic tool that has since shut down.
Why it took off It didn't take off on its own. What took off was a same-named extension the same team listed the day before the original stopped downloads (now renamed Open Research Button, about 30k users). Using the same name, a near-identical domain, and swapped-in backlinks from the old one, they captured the search traffic the original had built up over more than a decade.
CHow you could follow this Don't impersonate. Watch for well-known free tools that announce they're shutting down, list a version that clearly says "alternative to XX" before downloads stop, fill the gaps the replacement left, and ask the shutting-down party and library guides to swap their links for yours.
2,000 users · rating 5.0 (1)
Open Access Button was a free academic extension that ran for twelve years, and in November 2025 the nonprofit that ran it shut it down. The day before it stopped offering downloads, a small London team called PaperPanda listed a near-identical extension under the same name and registered a domain with just one extra hyphen, capturing the search traffic the name left behind. That extension has since been renamed Open Research Button and has about 30k users. The one in this story is the new same-named extension they listed in August 2026, which has 3 users after 2,000 months. The real thing to look at is the playbook, and why it's not worth copying.
Search the name and it's the first result
On Nov 6, searching "open access button chrome extension" on a search engine: #1 is the Open Research Button in the Chrome Web Store, #2 is a how-to guide from the Cold Spring Harbor Laboratory library, and #4 is open-access-button.org. The original site, openaccessbutton.org (no hyphen), is not in the top ten.
The Cold Spring Harbor guide has been rewritten in the past tense: "Open Access Button used to be a free, legal Chrome extension..." But guides from the University of Toronto and Western Michigan University, plus Wikipedia, still carry the name. A student who follows a teacher's guide and searches lands on this operator.
The hyphenated site's title reads "Open Access Button — Search 250 Million Research Papers," the first line says "Open Access Button is a free Chrome extension," and the button says "Add to Chrome — free." That button doesn't point to the new extension from this story. It points to the renamed Open Research Button.
How the original went away
Open Access Button launched in November 2013 and did something simple: when you opened a paywalled paper, it looked for a free copy in institutional repositories and legal sources like Unpaywall, and if it found nothing, it emailed the author on your behalf asking them to share one. It was later run by the nonprofit OA.Works.
On Jun 16, 2025, OA.Works announced on its blog that Oct 6 would see an end to new signups and Chrome / Firefox extension downloads, and Nov 18 would bring a full shutdown, with users advised to switch to Unpaywall. The blog also said: "As long as OA.Works is around, we will keep every domain we've ever used, to prevent abuse."
They kept openaccessbutton.org, but didn't anticipate someone registering a hyphenated version, and they left nothing behind in the Chrome Store.
What the new operator did
| Timeline | What happened | Sources |
|---|---|---|
| 2025-10-05 | PaperPanda's developer account listed a new extension named Open Access Button, with the URL path open-access-button. This was the day before the original stopped downloads. | Chrome Web Store release date |
| Around 2026-07-02 | Registered open-access-button.org: paper search, Google sign-in to save papers, AdSense ads on the page | Website privacy policy "Last updated 2 July 2026," web archive snapshots |
| 2026-08-07 | The extension was renamed Open Research Button, adding the line "One Button. Every Paper.™" | Chrome Web Store |
| 2026-08-09 | Two days later, a new extension was listed under the original name Open Access Button. This is the one in this story. | Chrome Web Store |
| 2026-11-06 | The official site's button still points to the renamed one. The new extension has 2,000 users and 1 ratings, and hasn't been updated since 11-01. | Chrome Store, official site |
No public explanation has been given for the rename or for opening a new one under the original name two days later. The most likely explanation is that the old extension drew impersonation complaints or was ordered to rename by store review, and the team opened a new one to reclaim the "Open Access Button" search term in the store (inference).
One more detail: Citationsy, a company linked to PaperPanda, lists Open Access Button on the recommendations page of its own site. The link text reads www.openaccessbutton.org, but clicking it goes to the hyphenated open-access-button.org. A link that originally pointed to the original has been quietly swapped for their own.
Who the team is
The developer listed in the store is PaperPanda, with an address on Blackfriars Road in London and a Gmail contact. The same account also has PaperPanda (70k users) and Open Research Button (30k). The paper search engine OA.mg is developed by Citationsy, also in London. The two share the slogan "Knowledge yearns to be free," both sites claim a library of "250M papers," and they recommend each other, listing each other as related extensions in the store. There's a strong case they're the same group, but no direct evidence (inference). Counting OA.mg's 20k users, this group has about 120k users in total for one-click paper PDF finding.
The extension is available in 19 languages. The store lists the primary languages of several extensions as Malay, Arabic and Thai, which suggests they're targeting students in non-English-speaking countries. I found no sign of paid ads or influencer promotion, just a few small YouTube channels focused on academic topics in India with videos like "how to download papers with PaperPanda."
Where the money comes from
The extension doesn't charge. The money is on the website: 250M papers, each with its own detail page carrying AdSense. The extension brings people to the site, and signing in with Google to save papers keeps them there. The extension is the entrance, the website is the ad slot. How much traffic the site gets and how much ad revenue it makes isn't visible from outside.
Functionally it's no different from Unpaywall (1M users), PaperPanda itself, or OA.mg: read the DOI on the paper page → check for a legal free version → download the PDF in one click. The original's "ask the author to share" feature was not carried over. Users stay because it's free, requires no sign-up, and works: Open Research Button has a rating of 4.36 out of 5 from 59 ratings.
Is anyone else competing?
| Product | User count (Chrome Store, November) | How it differs |
|---|---|---|
| Google Scholar Button | 4M | Google's own, covers full-text finding, citations and library links |
| EndNote Click | 8M | From Clarivate, distributed through schools |
| Unpaywall | 1M | The official replacement the original recommended, nonprofit, no ads |
| LibKey Nomad | 1M | Distributed through library subscriptions, installed school-wide |
| PaperPanda / Open Research Button / OA.mg | 70k / 30k / 20k | Same group |
| Open Access Helper | 6,000 | A German solo developer who wrote a blog post about the original's shutdown and addresses old users directly, without impersonating anyone |
| This listing: Open Access Button | 2,000 | Best name match, but the official site doesn't send it traffic |
This category is held by Google and a few big players with library channels. Nobody is chasing the name because this one company already owns it: the old extension, the new one, the lookalike domains. Hardly anyone has noticed, and only one third-party guide has a line saying it's "unclear how these two extensions relate."
If it were you
C. The name is already taken and this extension never took off. The thing to learn is the act of catching an established free tool that is shutting down. But the way this one does it (same name in the store, lookalike domain, borrowed external links) is impersonation. The store will make you rename, and this listing has probably been renamed once already.
Who it's for: indie devs who have shipped a plugin or small tool and are willing to watch every week for "who's shutting down." You should know the academic, open-source and non-profit tool circles, so you can tell which name carries a decade of backlinks and guides.
Who it's not for: anyone hoping to make a living from one extension (the money here is website ads, of unclear size, probably small inferred), or anyone unwilling to take on the risk of takedown complaints.
How to do it: take the honest route. Watch for well-known free tools announcing shutdowns (non-profit, academic and open-source projects are the most common, and they often post notices months ahead). The original code is often open source (OA.Works left its code on GitHub), so you can build a replacement that doesn't pose as the original but says plainly "XX has shut down, this is a continuation." List it before the original stops downloads, and build the one feature original users relied on that the replacement lacked. Here, that was "if we can't find it, ask the author to share."
How to get users: use "XX alternative" or "replacement for XX" phrasing to catch store search. Email library guide pages, Wikipedia entries and blog authors that still link the old name, and ask them to swap in your link. Ask the shutting-down team directly whether they'll list you as a recommended replacement. That single move beats any lookalike domain.
Deadline: there's no fixed one. It depends on the shutdown notice. From the announcement to the end of downloads there are usually a few months, and you must list before the download-stop date.
Where the read was off: (1) Open Research Button kept growing steadily a year after the original shut down (November was 30k), so the long tail of this name is longer than it looks. Catching a dead big name is worth more than a C. (2) Open Access Helper, which took over honestly (6,000 users), clearly grew over a few months. So capturing this traffic without impersonation works, and the honest path holds. (3) This listing or Open Research Button was taken down by the store for impersonation, yet this company's site still ranks ahead in search. That means the valuable assets were the lookalike domain and web search, not the name in the store.
Research notes: competitor table, acquisition evidence, full research report
- Competitors
Name Where Launched Scale How it differs from this one Unpaywall Chrome 2016-11 1M users / 289 reviews Non-profit, the replacement OA.Works officially recommends, self-hosted database, no ads. This listing only rides the original brand name for traffic. Google Scholar Button Big-company features 2015-04 4M users Made by Google. Finds full text, citations and library links. LibKey Nomad / Lean Library Chrome 2019 / 2017 1M / 200k users Runs through library subscription links and institutional promotion. EndNote Click Big-company features 2017 8M users From Clarivate, relies on institutional channels. PaperPanda Chrome 2024-08 70k users / 96 reviews Same team, same engine, under its own brand. Open Research Button Chrome 2025-10-05 30k users / 59 reviews Same team. This was originally the Open Access Button listing, renamed by 2026-08. The official site still sends traffic to it. OA.mg Web 2022 Chrome 20k users Possibly the same team (Citationsy). A paper-search engine version. Open Access Helper Chrome 2020-10 6,000 users Individual developer, takes over the original OAB's old users directly, without impersonation. Original Open Access Button (OA.Works) Other 2013-11 Shut down on 2025-11-18 The original also had a flow for requesting paper copies from authors. The successor only built the finding part. - Where users come from
- Verified name squatting / store search: a listing with the same name, dacjl, was published on 2025-10-05, the day before OA.Works stopped extension downloads (10-06). This listing 2026-08-09 reclaimed the name two days after dacjl was renamed.
- Verified lookalike domain SEO: open-access-button.org (with a hyphen) went live on 2026-07, titled Open Access Button, and ranks near the top when you search the original name. The original domain openaccessbutton.org is kept by OA.Works and only shows the shutdown notice.
- Verified swapping old backlinks: the anchor text on Citationsy's recommendations page reads www.openaccessbutton.org, but the link actually points to open-access-button.org.
- Verified cross-promotion matrix: the same account has 3 nearly identical extensions (PaperPanda 70k / ORB 30k / OAB 2,000), plus OA.mg, which appear as related extensions of each other in the store.
- Verified multilingual localization: 19 languages; listing_lang values are ms / ar / th (chromestore library).
- Inferred library guides and the Wikipedia long tail: LibGuides at CSHL, the University of Toronto and others still list Open Access Button. Users searching from them land here.
Research report: Open Access Button (Chrome, dpfbhlljgnjgijghhfodhambledljbja)
Bottom line: this listing itself never took off. It has 3 months of history, 2,000 users and 1 ratings. What's worth studying is the playbook behind it. The London team behind PaperPanda / Citationsy (which also runs OA.mg) opened a new listing under the same name on the day before OA.Works stopped offering the original Open Access Button extension for download (2025-10-05). They also registered the hyphenated domain open-access-button.org and captured the search, library-guide and backlink traffic. That listing has since been renamed Open Research Button and has about 30k users. 2026-08 Two days after the rename, they relisted under the Open Access Button name, which is this listing.
1. What it is
- Store page (read 2026-11-06): developer PaperPanda, Blackfriars Road, London SE1 8PB, non-trader, email [email protected]; version 2.4.0, last updated 2026-08-23, 60KB, 19 languages; official site open-access-button.org. Source: chromewebstore.google.com/detail/open-access-button/dpfbhllj…
- Function: reads the DOI from the paper page, checks whether a legal open-access version exists, and downloads the PDF in one click. The description is almost word-for-word from the team's own Open Research Button, with "ORB" swapped for "OAB." It closes with OA.mg's slogan, "Knowledge yearns to be free."
- Data (chromestore library item_snap): from 2026-11-01 to 11-06 it stayed at 2,000 users, 5.0 stars from 1 ratings, unchanged. Published 2026-08-09.
2. Key background: the original Open Access Button shut down
- The original OAB was built by David Carroll and Joseph McArthur, went into beta in 2013-11-18, and was later run by the non-profit OA.Works (casrai.org guide, 2026-08-29).
- OA.Works posted a blog on 2025-06-16 announcing the 2025-11-18 shutdown. 2025-10-06 stopped new sign-ups and Chrome / Firefox extension downloads, and recommended users switch to Unpaywall. OA.Works promised to "keep the original domain for as long as the organization exists, to prevent misuse." The original domain is openaccessbutton.org, without a hyphen. Source: blog.oa.works/sunsetting-the-open-access-button-instantill/
- Several universities' LibGuides (CSHL, University of Toronto, Western Michigan University and others) and Wikipedia still have "Open Access Button" entries. The name has over a decade of search volume and backlinks behind it.
3. How this team took over the name (timeline)
| Timeline | Event | Evidence |
|---|---|---|
| 2025-10-05 | The PaperPanda account published extension dacjlklfannlijcjfljgkieikajciabg, slug open-access-button (named Open Access Button at the time). This was the day before OA.Works stopped extension downloads. | chromestore library, published field. The official site CTA and the Google-indexed URL both use /detail/open-access-button/dacjl.... |
| 2026-07-02/03 | The hyphenated domain open-access-button.org went live (privacy policy "Last updated 2 July 2026", first Wayback snapshot 2026-07-03). The homepage CTA points to dacjl… with utm_source=OABWeb2. The site has a paper search ("250 million papers," the same index-size claim as OA.mg), Google login for a saved paper library, and AdSense ads plus GA. | Wayback snapshots 20260703 / 20260810; /privacy page |
| 2026-08-07 | Latest update to dacjl…; the name changed to Open Research Button (the description says ORB and adds "One Button. Every Paper.™"). | chromestore library, updated field; the current store page |
| 2026-08-09 | Relisted dpfbh… (this listing) under the original name Open Access Button, updated 2026-08-23 to 2.4.0. | chromestore library; store page |
| 2026-11 | The official site CTA still points to Open Research Button (dacjl), not to this listing. | Read the official homepage via r.jina.ai |
The reason for the rename wasn't disclosed, unverified. Relisting under the original name two days later suggests the most likely explanation: the old listing was forced to rename over trademark, impersonation complaints or store review, so the team opened a new listing to reclaim the "Open Access Button" store search term.
This team and OA.mg are the same people (high likelihood, not stated in the store):
- Citationsy (London; Citationsy Ltd is also OA.mg's developer) has a "Recommends" page that lists both OA.mg and PaperPanda. The entry recommending Open Access Button has anchor text reading www.openaccessbutton.org, but **the actual link goes to www.open-access-button.org/**. In other words, old backlinks that pointed to the original OAB were redirected to the new hyphenated domain. This is a classic SEO backlink hijack. Source: citationsy.com/recommendations
- OA.mg (Citationsy Ltd, 10 Marsh Wall, London) and PaperPanda (Blackfriars Road, London) are both in London and both use the "Knowledge yearns to be free" tagline. The store also lists them as related extensions of each other.
- The PaperPanda family has 3 extensions in the chromestore library: PaperPanda (bemeb…, published 2024-08, 70k users, 96 reviews), Open Research Button (30k, 59 reviews), Open Access Button (2,000, 1 reviews). Add OA.mg (20k), and this team has about 120k installs in the one-click paper PDF category.
Dark history: In 2025, a security blog and Reddit flagged that the “PaperPanda” extension with ID ggjlkinaanncojaippgbndimlhcdlohf, in its 2.1.6 version, had turned malicious: it pulled config from getxmlppa.com, hijacked search to search-yahoo-now.com, and tampered with Amazon pages (https://silocitylabs.com/post/2025/paperpanda-malicious/ ; r/chrome_extensions 1icxdez). The current PaperPanda is a different ID (bemeb…). Whether the old ID was sold or copied, unverified.
4. Competitors
| Name | Where | Launched | Scale (chromestore library, 2026-11) | How it differs |
|---|---|---|---|---|
| Unpaywall(OurResearch) | Chrome | 2016-11 | 1M users / 289 reviews | Non-profit, the replacement OA.Works officially recommends. Runs its own OA database and auto-pops tags beside the page. No ads. |
| Google Scholar Button | Chrome (big tech) | 2015-04 | 4M users / 1,431 reviews | Made by Google. Covers finding full text, citations and library links. |
| LibKey Nomad / Lean Library | Chrome | 2019 / 2017 | 1M / 200k | Goes through library subscription links, pushed by institutions. |
| EndNote Click (Clarivate, formerly Kopernio) | Chrome (big tech) | 2017 | 8M | Big tech + institutional channels |
| PaperPanda (same team) | Chrome | 2024-08 | 70k users / 96 reviews | Same engine, own brand. |
| Open Research Button (same team, the original OAB listing name) | Chrome | 2025-10-05 | 30k users / 59 reviews | The predecessor of this listing, and the main traffic driver. |
| OA.mg(Citationsy) | Chrome + web | 2022 | 20k users / 27 reviews | The search engine version from the same team. |
| Open Access Helper Web(Claus Wolf) | Chrome / iOS / macOS | 2020-10 | 6,000 | An individual developer. Took in users of the original OAB and wrote a blog post about the OAB shutdown (oahelper.org 2025-10-18). |
| Open in Sci-Hub and others | Chrome | 2021–2022 | Under 20k | Relies on pirated sources. This listing pitches itself as “legal.” |
| Original Open Access Button (OA.Works) | Chrome / Firefox / web | 2013 | Shut down | The original also had a “ask the author to share” request flow. The takeover version has no such feature. |
5. Growth tactics (evidence)
- Riding the brand + store name search (confirmed): The day before the original extension stopped downloads, this one went up under “Open Access Button.” When users search the original name in the store, it's the only one left.
- Near-domain with a hyphen, for SEO (confirmed): open-access-button.org ranks near the top for “open access button” on Jina and Google, and its page title and H1 both say “Open Access Button.” The original domain openaccessbutton.org is still held by OA.Works and only shows the shutdown notice now.
- Rewritten outside links (confirmed in 1 cases): In Citationsy's recommendation page, the link to the original OAB was swapped to the new domain. Other university LibGuides still use the original name, so users who follow them and search will land here too.
- Multilingual (confirmed): the store listing is in 19 languages. The chromestore library records listing_lang as ms (Malay) for this one, ar (Arabic) for Open Research Button and th (Thai) for PaperPanda, suggesting localization aimed at students in non-English regions.
- Matrix (confirmed): one account runs 3 near-identical extensions plus OA.mg, and their “related extensions” in the store send traffic to each other.
- Ads, creators, X (not seen): x-radar finds no mentions of paperpanda or open research button in the past year. No evidence of paid promotion. A few small YouTube videos from Indian academic channels titled something like “how to download papers with PaperPanda” exist.
6. Why it took off (this is about the “name,” not this listing)
- Timing: a well-known academic tool brand with over a decade of accumulated use shut down, the official side only recommended Unpaywall, and did not reclaim the search terms. A small team put up a same-name extension the day before the shutdown and caught the long tail of searches from original users and library guides.
- Why users stayed: the core function matches the original (read DOI → find OA version → download PDF). It's free and needs no sign-up. For students, “one click to get the PDF” is enough. Rating 4.36 (59 reviews) shows the product works.
- Where the money comes from: the extension itself is free. Its site says AdSense + GA, earning ad traffic from the paper search and paper detail pages on the website. The 250M-paper pages are themselves material for programmatic SEO. The extension pulls users onto the site to log in and save their paper libraries.
Why this dpfbh didn't take off: the official site's CTA still points to the old listing (dacjl), so this one only gets the small share of traffic from people searching the original name in the store. Live for 3 months with 2,000 users, growth is very weak.
7. Differentiation
On product features it has almost no differentiation. Unpaywall, OA.mg and PaperPanda all do “DOI → OA version.” The only real difference is the name: it's called “Open Access Button.” That difference is why it gets traffic. The hyphenated domain also links extension traffic, site SEO and AdSense into one monetization chain, which differs from the non-profit Unpaywall.
8. Visibility
- Revenue is not public. No media outlet or big X account has written about it.
- Only one guide from purplelink.llc (2026-10-04) noticed that Open Research Button comes from a different publisher, PaperPanda, and wrote “I haven't figured out the relationship.”
- Bottom line: few people know about it yet. The small circle that follows academic tools (librarians, guide writers) has sensed something is off, but no one has called it out.
9. Copycats
No one else has been found grabbing the “Open Access Button” name. The store has small copycats from the same period, such as “Sci-Hub Mirror Quick Access” (2026-08), but they use pirated sources and don't count as the same play.
10. Takeaways
- Target well-known free tools with existing search traffic that are shutting down (non-profit, academic and open-source projects are the most common). Around the time the official side stops distribution, publish an extension with the same or a near name, register a near domain, and rewrite the outside links you can control, to catch branded search. The cost of this is very low.
- Use the extension as the entry point to a website, monetized with programmatic SEO (paper pages) plus AdSense. No paid tier needed from users.
- Risks: possible trademark or impersonation complaints forcing a rename (likely what happened here); the same account's old malicious extension history will drag down trust; Google may take down “impersonation”-type listings.
11. Uncertain
- What directly caused dacjl's rename (an OA.Works complaint, or store review?).
- Whether PaperPanda, Citationsy and OA.mg are the same legal entity (for now only indirect evidence: copy, address region, cross-promotion, outside links).
- The relationship between the malicious ggjlk… version and today's PaperPanda.
- How many users the original OAB extension had when it shut down, and how much traffic and AdSense revenue the hyphenated-domain site gets.
- The recall card's claim that it “reused the original OAB extension ID” is not true: dacjl was published on 2025-10-05, so it is a newly created listing, not an acquired old one.
Sources
- chromestore library (agent-im server, snapshots 2026-11-01 to 11-07): item / item_snap / developer
- chromewebstore.google.com/detail/open-access-button/dpfbhllj…
- chromewebstore.google.com/detail/open-research-button/dacjlk…
- blog.oa.works/sunsetting-the-open-access-button-instantill/
- casrai.org/guides/open-access-button
- www.open-access-button.org/, /privacy; Wayback 20260703144016, 20260810065020
- citationsy.com/recommendations
- oa.mg/
- purplelink.llc/guides/best-chrome-extensions-for-google-scho…
- silocitylabs.com/post/2025/paperpanda-malicious/; www.reddit.com/r/chrome_extensions/comments/1icxdez/
- www.oahelper.org/2025/10/18/oa-works-will-sunset-open-access…