Core Viewpoint - Anthropic has cut off OpenAI's access to its Claude API, accusing OpenAI of breaching service terms by using Claude to support the development and safety testing of the upcoming GPT-5 model, indicating a new phase of competition and data/interface lockdown in the AI industry [1][4][10]. Group 1: Actions and Reactions - Anthropic's spokesperson stated that OpenAI's use of Claude for internal tools violated their service terms, which prohibit using their services to build competing products or reverse-engineering [9][12]. - OpenAI expressed disappointment over the ban, emphasizing that evaluating other AI systems is a common industry practice and highlighting that their own API remains open to Anthropic [14]. - Anthropic's contradictory statement about allowing OpenAI access for benchmarking and safety assessments raises questions about their intentions [14]. Group 2: Competitive Landscape - The incident reflects a broader trend in the tech industry where companies use API access as a strategic weapon against competitors, similar to past actions by Facebook and Salesforce [15]. - Anthropic's decision to revoke access is seen as a tactical move in the escalating competition for AI dominance, particularly as OpenAI prepares to launch GPT-5, which is rumored to have enhanced programming capabilities [10][19]. - The AI sector is entering a phase where APIs are not just technical details but strategic resources crucial for market access and innovation freedom [19]. Group 3: Market Implications - The recent actions by Anthropic highlight the intensifying competition in the AI space, with companies increasingly focusing on data and interface control as a means to secure their market position [19][20]. - The situation underscores the potential for regulatory scrutiny as the industry grapples with issues of access and competition [19].