Communist Cuba's newfound interest in foreign capital has its limits, as Philippe Pouletty found out.
A French doctor, venture capitalist and founder of biotech company Abivax, Pouletty is working with Cuba's Center for Genetic Engineering and Biotechnology to develop a therapeutic vaccine to treat chronic Hepatitis B that could be on the Asian market in two years and in Europe after that.
But when he pitched the idea of floating a company on the pan-European stock market Euronext with the Cuban state as a shareholder, that was clearly too much, too soon.
"I told him in a half serious, half joking mode, that I had a capitalist proposal," Pouletty said of his conversation with Cuban revolutionary leader Fidel Castro's eldest son, Fidel Castro Diaz-Balart, a science advisor to the government.
"His response after more than 30 seconds was 'That's indeed very intriguing, but if you want us to reach an agreement quickly, that's not the fastest route. It's a few years too soon'."
Instead, Abivax agreed to buy vaccines at a predetermined price and pay royalties to Cuba when the product is on the market. Pouletty's story offers a peek into the mindset of Cuba Inc.
Convinced their country needs capital, Cuba's leaders are welcoming businesses under a foreign investment law passed a year ago, but they want tight control over the pace of change.
US business interest in Cuba has exploded since December, when President Barack Obama and Cuban President Raul Castro announced they would restore diplomatic relations after decades of hostility.
"In the morning on December 17, Cuba was still a word spoken in US business circles with hushed tones. By the afternoon, half of corporate America was rambling around forming a Cuba team," said Mark Entwistle, a former Canadian ambassador to Cuba and now a partner at Toronto-based merchant bank Acasta Capital.
Among those joining a recent New York state delegation to Cuba were executives from JetBlue Airways Corp, Pfizer and MasterCard.
Most US companies are still blocked by the 53-year-old trade embargo, although Obama has relaxed it for some imports, travel and telecommunications. That has allowed for minor deals such as Netflix streaming movies in Cuba and Airbnb listing Cuban rental properties online.
If Obama can convince Congress to end the embargo, US firms would be free to do business here, though they would still face major obstacles, including a multi-layered bureaucracy, an unpredictable legal system and highly regimented labour market.
Many foreign companies have thrived over the years. They run hotels, build ships, refine oil and pack meat. Some have a share in bottled water, beer, soda, rum and cigar businesses.
Canada's Sherritt International is perhaps the most established. It has been here since 1992 and generated 73pc of its revenues in 2014 from Cuba-related businesses.
Sherritt mines nickel in Cuba and refines it in Canada in a 50-50 joint venture with Cuba's government. It also produces 20,000 barrels per day of oil that it sells to Cuba and has a one-third interest in an electricity joint venture.
Even in a business subject to price swings, Sherritt says it has always made a profit or at least broken even with Cuban nickel.
"We would tell others that Cuba's a great place to do business," said Sean McCaughan, vice-president for investor relations, even though the embargo means top Sherritt executives are banned from setting foot in the United States and the company is cut off from US capital markets or shipping through US territory.
Other companies have failed miserably in Cuba and were forced to leave or had their executives imprisoned and their assets confiscated. Petty bribery can land people in jail.
Those who have been successful have simple advice: be flexible and listen to Cuban officials, because they will tell you exactly what they want.
There is no escaping the state's central planning. Foreign firms in joint ventures must order raw materials a year ahead of time. Property is leased from the state, not up for sale.
Cuba regularly draws up a portfolio of projects it wants foreign help with. The latest, issued in November, outlines 246 mostly joint ventures, that need investments totalling $8.7bn.
In tourism, the portfolio lists five hotel construction projects; two golf developments; and contracts to manage 33 hotels.