The Greek branch of Transparency-International said a $3400 donation it received from the Swiss pharmaceutical company Novartis came before the business was accused of bribing 10 rival politicians of the ruling Radical Left SYRIZA.

Prime Minister Alexis Tsipras said his rivals took money without offering any proof and declared them guilty although the case is based on the uncorroborated testimony of three whistleblowers, two of who remain anonymous.

Some of the accused, a list that include two former Premiers and Bank of Greece Gov. Yannis Stournaras and the European Union’s migration chief, Dimitris Avramopoulos, have brought suit, saying they were slandered and demanding to know the names of their accusers.

Anna Damaskou of Transparency International Greece acknowledged the donation, but noted that her group joined a call for an investigation into the alleged scandal and And Michael Hornsby, a spokesperson for Transparency International in Berlin, said Novartis made the donation to TI-Greece “several years prior to the current scandal surrounding their alleged bribery of officials in Greece.”

The revelation was made by the Greek paper Dimokratia which said the corruption scandal was already being probed in 2013, two years before SYRIZA came to power, but that it didn’t come to light until later.

Transparency International Greece has taken corporate donations over the years from major multinational corporations, including Lockheed Martin, Coca-Cola, Nestle, Unilever, KPMG, PWC, Ernst & Young and GlaxoSmithKline, the paper said, suggesting the organization could be co-opted by taking money from businesses.

In January 2017, Transparency International USA was stripped of its accreditation. The group had increasingly come to be seen in the United States as a corporate front group, funded primarily by large multinationals, including Bechtel Corporation, Deloitte, Google, Pfizer  ($50,000 or more), Citigroup, ExxonMobil, Fluor, General Electric, Lockheed Martin, Marsh & McLennan, PepsiCo, PricewaterhouseCoopers, Raytheon, Tyco ($25,000–$49,999), and Freeport-McMoRan and Johnson & Johnson (up to $24,999).

Last year, the German Chemical Industry Association, a partner of Transparency International, lobbied European Union officials in opposition to stronger rights for whistleblowers while BlueprintGreece, affiliated with the Australian-based group Blueprint for Free Speech was set up to combat the phenomenon in Greece and the EU.

In 2013, Transparency International Berlin accepted a $3 million donation from Siemens, although the company pleaded guilty in 2008 to bribery charges and paid more than $1.6 billion in penalties and has been in a long-running bribery scandal in Greece.