Rishi Sunak has changed his expenses declaration over the funding of private jet travel to Tory events after questions were raised about why they were recorded as coming from a small company linked to a multimillionaire businessman. Sunak’s latest declaration now names the donor of £38,500 to pay for air travel by the prime minister and staff as Akhil Tripathi, a British-Indian medical tech entrepreneur who made a fortune from an anti-snoring device. Tripathi had previously donated to the Conservatives in 2021 and 2022. The declaration lists his address as “private”. The change is the third time that the declaration has been updated by the prime minister and comes after Labour wrote to two standards watchdogs to ask if any rules had been broken over declarations of more than £88,000 over the past eight months for air travel by the prime minister and direct funding to the Tory party. Sunak had previously declared that the air travel – for him and eight staff to attend Conservative events in Scotland and Wales in April – was funded by Balderton Medical Consultants, a one-man business whose address on the donations register was given as a west London property. However, Land Registry records show that the property in Belgravia is owned by a firm based in the British Virgin Islands and Jersey. This firm’s beneficial owner is Akhilesh Shailendra Tripathi. When the Guardian visited the property, a person who answered the door said it was not the address of Balderton Medical or of its sole director. Asked if the property was the house of Akhil Tripathi, the person said: “Yes.” Emily Thornberry, the shadow attorney general, said on Thursday that Sunak “made a deliberate decision” in early June to change his declaration regarding the donation for the air travel, “and he only changed it back again a month later after people started raising questions”. “On the face of it, that first change now looks like a conscious breach of the rules on political donations, and it requires an immediate and credible explanation from the man who made it,” she added. Labour has also been calling for scrutiny of a £50,000 donation from Balderton which was declared by Conservative Campaign Headquarters (CCHQ) to the Electoral Commission in November 2022. It used an address in the Leicestershire market town of Lutterworth, which is the firm’s Companies House address. However, in the wake of the Sunak update on the funding of his air travel, Thornberry questioned whether the Tories still maintained that Balderton was the true source of the £50,000, “or whether that is a third declaration from the company that will require both correction and explanation”. The Conservative party has been approached for comment. When it was approached by the Guardian earlier this month with questions about Sunak’s earlier declarations for his air travel, a spokesperson for the party said: “This donation in kind was processed by the Conservative party, and the information then provided to the prime minister’s office. “CCHQ will now review the information provided. If necessary, any administrative errors will be corrected.” A spokesperson for Tripathi’s company, Signifier Medical Technologies, has previously said: “We don’t have any comments or information to offer regarding this situation.”