The government may be about to risk billions of pounds in lawsuits, as it mulls whether to ban branded cigarette packets.
During the consultation, which ended overnight, tobacco companies warned the health secretary the move would amount to the "expropriation" of the industry's intellectual property.
"I can see no reason why depriving someone of his proprietary interest in a trade mark for a tobacco product (however much it may be in the public interest to do so) should be different in principle from any other deprivation in which compensation is required," legal opinion by Lord Hoffmann provided for the consultation by tobacco giant Philip Morris said.
Australia became the first country to impose blanket plain packs recently and is now facing significant legal challenges.
Anti-smoking groups insist a ban would see fewer young people take up the habit.
"Plain, standardised packaging of its lethal products frightens 'big tobacco' silly because it threatens its profits," Deborah Arnott, chief executive of campaign group Ash, said.
"That's why the industry has devoted millions of pounds to put pressure on politicians and prevent the government from going ahead with this measure."
Lansley is thought to be wary of the move but insists government's have a duty to investigate any possible ways of reducing smoking.
The health secretary is a confusing figure for the tobacco industry. On the one hand he is usually opposed to regulation, as he demonstrated during rows about salt content in food.
However, some of his comments on the smoking issue have been distinctly combative, including the assertion that tobacco companies have "no business" in the UK.
"We have not yet analysed all the responses but have already received a substantial number," a Department of Health spokesperson said.
"We have an open mind on this issue and will make a decision on any further action after we have considered the responses, evidence and other relevant information."
If the law was passed the packets would be likely to be olive green, which is apparently the colour least attractive to smokers.
With advertising and many marketing avenues shut off to tobacco companies, packaging is one of the few ways they have left of differentiating their products.