Introduction Transnational tobacco companies (TTCs) submitted evidence to the 2012 UK Consultation on standardised packaging (SP) to argue the policy will have detrimental economic impacts and increase illicit tobacco trade.

Methods A content analysis of the four TTC submissions to the consultation assessed the relevance and quality of evidence TTCs cited to support their arguments. Investigative research was used to determine whether the cited evidence was industry connected. Fisher's exact tests were used to compare the relevance and quality of industry-connected and independent from the industry evidence. The extent to which TTCs disclosed financial conflicts of interest (COI) when citing evidence was examined.

Results We obtained 74 pieces of TTC-cited evidence. The quality of the evidence was poor. TTCs cited no independent, peer-reviewed evidence that supported their arguments. Nearly half of the evidence was industry-connected (47%, 35/74). None of this industry-connected evidence was published in peer-reviewed journals (0/35) and 66% (23/35) of it was opinion only. Industry-connected evidence was of significantly poorer quality than independent evidence (p<0.001). COIs were not disclosed by TTCs in 91% (32/35) of cases.

Conclusions In the absence of peer-reviewed research to support their arguments, TTCs relied on evidence they commissioned and the opinions of TTC-connected third-parties. Such connections were not disclosed by TTCs when citing this evidence and were time consuming to uncover. In line with Article 5.3 of the Framework Convention on Tobacco Control and broader transparency initiatives, TTCs should be required to disclose their funding of all third-parties and any COIs when citing evidence.