Mr Paterson said he had fully declared all his financial interests in the House of Commons register. It comes after The Guardian reported that he helped lobby the Government on behalf of a firm he is paid to advise.
The newspaper said Mr Paterson, a former cabinet minister, had helped a company he worked for to lobby the Government over public contracts.
Mr Paterson is paid £98,000 a year for work as a consultant to Randox, a private forensic testing company.
The Guardian reported that Mr Paterson and Randox lobbied the Department for International Development to secure contracts from the department.
But Mr Paterson said he had broken no rules and, as far as he was aware, no complaint had been made about his work for the company.
He said: “My financial interests have been correctly declared according to the rules of the House of Commons.”
House of Commons rules state that an MP may lobby on behalf of a paying client, but must not help to give an exclusive financial benefit to the client, and the client must not have initiated the lobbying.
Documents obtained under the Freedom of Information Act show that in July 2016 Randox wrote to Priti Patel, then the International Development Secretary, asking for a meeting.
The company wanted to discuss the healthcare diagnostics it was able to provide, and outlined the advantages of its products, according to the documents.
Mr Paterson and a representative of Randox held a meeting with Rory Stewart, then a junior international development minister, with officials in January 2017.
Files on the meeting recorded: “This meeting covered Randox’s laboratory quality assurance systems, the department's broad approach in health, and procurement routes and potential commercial opportunities that Randox may wish to explore.”
The note added that the department did not fund Randox either directly or as a major subcontractor.
"The department's support for health does not typically include direct funding for the laboratory equipment, or associated quality assurance products and services that Randox provides."
It said the department had no immediate opportunities for the company, but added: "We are helping connect Randox, as a British company with a strong shared interest in improving quality of healthcare in developing countries, with other potential commercial opportunities they may wish to bid for.”
According to the parliamentary code of conduct, MPs can take part in lobbying for a client provided that “their approach or participation does not seek to confer benefit exclusively on that person or organisation (or on their client) and provided that that person or organisation (or their client) has not initiated the event”.