Nanex sells market data and tools for analyzing market data.<p>Historically (I haven&#x27;t looked in a long time) their market data was inappropriate for HFT usages as it was not at the fidelity required for those applications, but it was very cheap in comparison to other market data providers.<p>This led to a natural segmentation of their market such that most of their clients are people who are a) interested in market structure but b) not interested in high fidelity market structure information and who aren&#x27;t interested enough to spend more on other options.  That frequently is large block traders (hedge funds) who have a natural opposition to HFT market makers.<p>Whether that is the only factor in their strident anti-HFT position or if they have other personal moral reasons for it as well, they also publish a highly biased blog railing against HFT, but that is not their business.<p>In the industry, I never encountered them in the context of &quot;highly respected financial research firm&quot; and only in the context of &quot;dirt cheap market data archive&quot;.