CyanoGuard and the EIC Accelerator: Cyanide IP Passes to Cyanco

CyanoGuard AG no longer exists. The Zurich company, a 2016 spin-off built on cyanide-sensing chemistry from the University of Zurich, was dissolved by a resolution of its general meeting on 23 November 2023, and after the liquidation was completed it was deleted from the commercial register on 16 October 2025, according to the Swiss federal register Zefix and the Zurich cantonal register excerpt. The company closed through a voluntary liquidation, not a bankruptcy: the register shows no insolvency proceedings.

Four years earlier, CyanoGuard had been one of the winners of the EIC SME Instrument Phase 2 cut-off of 5 June 2019, the Horizon 2020 round that preceded the EIC Accelerator pilot. The European Commission's list of selected companies names CYANOGUARD AG alone for the project CyanoSmart, with no partner company. CORDIS records an EU contribution of €1,553,749.75 towards a total cost of €2,219,642.50, for a project that ran from 1 November 2019 to 30 April 2022. The goal was a handheld, connected cyanide analyser for gold mines. That analyser was built, certified and shipped. Then the company was wound up, and its core patent family ended up with Cyanco, the American producer of the very chemical CyanoGuard's device was meant to help mines use less of.

A Colour Test for the Most Important Reagent in Gold Mining

Most gold is leached out of crushed ore with a dilute cyanide solution. Too little cyanide leaves gold in the tailings; too much wastes money and raises the cost of detoxifying the waste. CyanoGuard's project summary on CORDIS says cyanide costs "often exceed 70% of the total processing costs" of a mine and that mines lose "$5B in recoverable gold each year" through poor process control. Those are the company's figures, not independent estimates.

The usual method, the company's final report says, is manual titration, often in a laboratory, taking "at least 4-6 hours" and prone to interference; fixed online analysers are faster but expensive to install and maintain. CyanoGuard's answer had three parts: a single-use test cartridge (CyanoKit) that changes colour with the cyanide concentration, a handheld reader (CyanoSmart) that turns the colour into a number, and a cloud platform that collects the readings and can send alerts by SMS or WhatsApp. The chemistry is protected by a patent family on a test kit with a solid buffer set to a pH of 9 to 10, which avoids diluting the sample and shows interfering metal ions as a precipitate, according to the European patent and its US counterpart, both naming Kirchgässler, Cherbuin and Marjorie Sonnay as inventors.

The size of the benefit moved with the audience. In April 2020 the company told International Mining its technology enabled a 12% reduction in cyanide use. In March 2021 it told Startupticker 15 to 20%. Its 2022 report to the EU says 15% on average plus 2% more gold recovered. None of these figures comes with published mine data.

What CyanoSmart Promised, and What the Report Shows

The EIC proposal set out to "develop the CyanoSmart to scale for the benefit of the entire gold mining industry", taking the prototype to an industrialised system, according to CORDIS. The grant agreement was signed on 22 October 2019 and the project ended on schedule on 30 April 2022, 30 months after it began. It followed a €50,000 SME Instrument Phase 1 feasibility study, CyanoKit, which ran from November 2017 to February 2018 and was the subject of a CORDIS news feature. CORDIS lists no other EU project for the company.

The final periodic report, covering November 2020 to April 2022, says the automated cartridge line received ISO 9001 certification and was producing "at a capacity of 30,000 cartridges per month", that serial production of the reader had started "with around 75 meters being manufactured", that the reader received CE marking, and that the product "has been delivered to 17 mine sites" where pilot testing began. "Several customers", it says, became regular users. The report also concedes that "further development steps are required": linking the readings to a control system, automating sampling and adding other sensor data.

Independent coverage confirms the CE marking and pilots. In July 2021 International Mining and EIT RawMaterials reported the CE certification of the latest CyanoSmart analyser, a measuring range of 0.1 to 4,000 ppm of free cyanide, pilots in Brazil, Colombia, Mexico and Peru, and an installation overseen by NALCO Water, an Ecolab company, at a gold mine in Antioquia, Colombia. The production figures, the ISO 9001 certificate and the count of 17 sites appear only in the company's own report.

1. Industrialised handheld readerDeliveredCE marking reported by the company and by International Mining.
2. Automated cartridge productionCompany-reportedISO 9001 and 30,000 cartridges a month, stated only in the final report.
3. Cloud monitoring platformCompany-reportedDescribed as in regular customer use; no outside account.
4. Roll-out to gold minesPartial17 sites, mostly pilots; named projects at KCGM, Agnico Eagle Finland and with Ecolab.
5. 15% less cyanide per mineUnverifiedClaim varied from 12% to 20%; no mine data published.
6. A business at industry scaleNot achievedCompany dissolved in November 2023.

The Money Around the Grant

CyanoGuard announced a seed round of more than CHF 3 million on 14 April 2020, led by Wingman Ventures with BlueOcean Ventures; Wingman partner Alex Stöckl joined the board, according to International Mining and EIT RawMaterials. In March 2021 Prospect Mining Studio, a programme of Newlab and the Vimson Group, invested USD 0.5 million, which the company said brought its extended seed round to more than USD 3.5 million, according to Startupticker and EIT RawMaterials. The same announcement said three of the world's ten largest gold producers were early adopters and named projects at KCGM in Australia, Agnico Eagle in Finland and Ecolab in Colombia.

The commercial register tracks this. Share capital rose from CHF 126,600 to CHF 158,198 in April 2020, when Seed 1 and Seed 2 preference shares were created and CHF 284,870.04 of claims were converted into shares, and to CHF 169,337 in January 2021 with a Seed 3 class, according to the register entries in Zefix. No later capital increase was registered. No round after the seed extension has been announced, and no revenue or staff figures were ever published. The EIC Fund did not invest: CyanoGuard does not appear on any of the 16 pages of the EIC Fund's list of invested companies, and its 2019 award was grant only.

How It Ended

The register shows the company coming apart in stages. Its seat moved from Wädenswil to Badenerstrasse 790 in Zürich in February 2022. Alex Stöckl left the board in December 2022; co-founder Benedikt Kirchgässler's board seat was struck off in March 2023, as was that of Benjamin Megerle. In April 2023 the two remaining directors, William Dougherty and Jodok Reinhardt, were given sole signing rights; in May the address became c/o Fitis Treuhand AG, a fiduciary firm, and an auditor was appointed. On 23 November 2023 the general meeting dissolved the company and named Dougherty and Reinhardt liquidators. The liquidation was declared complete and the company deleted on 16 October 2025, per the cantonal excerpt. No public statement from the company or its investors explains the decision, and the cyanoguard.ch website did not load when checked for this article.

One small inconsistency: CORDIS gives the coordinator's address as Badenerstrasse 790, 8048 "Wadenswil", while the register places that address in Zürich.

Where the Technology Went

The clearest trace of what happened to the technology is in the patent records. The US patent 11,609,213, granted to CyanoGuard on 21 March 2023, was assigned on 10 January 2024 by "Cyanoguard AG in liquidation" to Cyanco Holding Corp., according to Google Patents, which reproduces the USPTO assignment record. The matching European patent, EP 3622286 B1, was granted on 2 July 2025 with Cyanco Holding Corp as the proprietor, per its record. Whether Cyanco also took over staff, customers or the CyanoSmart product, and what it paid, has not been disclosed by either side; no acquisition announcement could be found.

Cyanco is not a monitoring start-up but a cyanide maker. In 2013 it called itself "the largest global producer of sodium cyanide" after opening a plant in Alvin, Texas, in a press release, and in a 2022 interview with GBR it described an Applied Technology team that works with mines on "optimization of the entire cyanide circuit". A test that helps mines dose less cyanide fits a supplier's service offer; whether Cyanco sells it today could not be verified.

Why It Matters for Europe

Cyanide in mining is a European political issue. After the 2000 tailings dam failure at Baia Mare in Romania, which the CyanoSmart report itself cites, the European Parliament on 5 May 2010 voted 488 to 48, with 57 abstentions, for a complete ban on cyanide mining technologies in the EU, according to the Legislative Observatory; the Commission did not propose one, as Mediafax reported. EU law instead caps weak acid dissociable cyanide at the discharge into tailings ponds at 10 ppm for new facilities, and for older ones since 1 May 2018, under Article 13(6) of the Mining Waste Directive. Tools that measure cyanide on site serve exactly that rule, and one of CyanoGuard's named projects was at Agnico Eagle in Finland, an EU gold producer.

The outcome is less favourable to Europe's technology base. A Swiss university invention, developed with €1.6 million of EU grants across two projects and backed by the EIT RawMaterials accelerator, ended with its European and US patents owned by a US company. That transfer is legal and may keep the technology in use, but the EU-funded venture that was meant to scale it did not survive.

The Verdict

CyanoGuard's former directors, Cyanco and the EIC were not asked for comment for this article. It is based on public records and published statements, linked throughout.