Gideon Summerfield, managing director of Pioneer Online, a subsidiary of science indie Pioneer Productions, said he was frustrated by broadcasters' protective attitudes towards their specialist content, which he said denied viewers access to hard-to-find material.
'At this stage in the growth of video on the web, broadcasters need to take a strategic decision to nurture the online market,' he said. 'But they're just replicating what they do on terrestrial TV, which means this kind of content can get lost.'
He said the likes of National Geographic and Discovery are brands in their own right and are reluctant to relinquish rights because they want to be seen to be hosting content, while the BBC and Channel 4 are slowed down on rights clearance by a lack of resource.
FirstScience.tv, which had a soft launch in May, now hosts 85 titles and aims to expand its catalogue to more than 400 by its full launch at the end of the year. Content on the site is mostly three to 10 years old and is offered on a rental or download-to-own basis.
However, due to rights issues, only half of the titles are accessible to UK viewers, whereas US users can view more than two thirds of them. The US now represents around three quarters of sales and generates 60% of the site's traffic.
'With US contracts in particular, it's very tough to get UK rights,' Summerfield said. 'Anything more than five years old from Pioneer is pretty much out of bounds to us now. It tends to be tied up with the likes of National Geographic.'
Rights clearance is clouded -further by the fact that many bigger budget science docs are co-productions, he added.
'Traditionally with co-productions, it's been unlikely that someone would have made the effort to get the new media rights, leaving it to one party to exploit later,' he said.
'We're starting to see partners negotiate them as the contract is signed, but there's often not enough in it for one of them to fight for the rights. They're more interested in tying up territorial broadcast rights.'
Once FirstScience.tv is established, Pioneer Online wants to move into other areas of specialist factual, seeing a market for areas such as travel and health online.