The satellite platform holder yesterday published its second formal submission to the BBC Trust in reaction to the additional information recently supplied by the BBC Executive.
In the report, Sky stated its belief that the BBC's plan for Canvas confirms its "apparent intention to develop, launch and operate an entirely new content distribution platform together with a limited number of competitor venture partners, for mutual benefit, to the exclusion of other industry participants".
Sky claimed that the development of a Canvas IPTV platform goes beyond the BBC's role as defined in the Royal Charter. It therefore asked the Trust to properly consider whether the proposals are an appropriate use of the licence fee, or if there is adequate consumer demand for a Canvas box, before granting its approval.
"In its unique, privileged position in receipt of substantial guaranteed public funding, the BBC is also required to adopt the least intrusive, proportionate means of fulfilling its core purpose, and to minimise any distortions of competition that might arise from the commercial deployment of its public funding," said Sky in its report.
The company is further concerned about Canvas membership - BBC, Five and ITV - due to fears that only public service broadcasters will be permitted to join, with BT's participation only complicating the issue.
This complaint taps into Sky's fears that Canvas partners will favour their own content on the platform when it launches to the detriment of other services. In turn, it reiterated concerns about control of any Canvas user interface or EPG, particularly due to the "standardisation" of this feature which could reduce innovation and competition.
Sky further criticised the lack of technical specification in the BBC Executive's released information, which poses questions about whether Sky Player would work on the box and what sort of content protection would be available. It also questioned how much public money is actually being spent on developing the project in the absence of confirmed figures.
As an alternative approach, Sky believes that the BBC should drive forward development in the IPTV market by implementing a "genuinely broad policy of linear and on-demand content syndication across third-party platforms and services".
Back in August, BBC programme director, IPTV Richard Halton accepted that the open source platform of Canvas could be viewed as an "absolute disaster" for pay TV providers.
However, he stressed that the platform would be designed to maximise creative freedom for a wide variety of service providers, and not prioritise the content of its partners as it would be "very naive for us to do something so obvious".