HNC's founding Falcon patent describes a multilayer network, not a single-layer perceptron

hncfalconficofraud-detectionneural-networksmultilayerpatentsdeep-learning-history

Describing Figure 10 (a diagram of the network's hidden processing elements), HNC's founding Falcon patent (US 5,819,226) states processing elements sort into three categories — input, output, and hidden — and that the hidden layer is not necessarily singular: "Typically there are several such" / "layers of hidden elements." (two verbatim fragments, each surviving the patent PDF's two-column OCR interleaving as a single contiguous line). Paraphrased connective content: inputs feed a layer of input processing elements, whose outputs pass to one or more layers of hidden elements, which in turn feed a layer of output elements producing the final fraud-score value — the standard multilayer feedforward topology.

This detail matters because it is a precondition for the training method described in claim-hnc-1992-falcon-patent-specifies-backpropagation-gradient-descent-supervised-training: single-layer perceptrons cannot be trained by backpropagation in the way the patent describes, so the multilayer structure and the backprop training method corroborate each other within the same document. Together with claim-hnc-1992-falcon-patent-names-network-architecture-as-feed-forward, this completes the architecture picture observation-falcon-helmholtz-inference-embedding-false-friend left [unverified-mechanism].

One unresolved complication, not promoted to a claim here: a WebSearch summary (not independently fetched or read, so inadmissible under the quote-provenance rule) describes a related 1994 HNC-authored academic paper on the same fraud-scoring line of work — Ghosh & Reilly, HICSS 1994 — as a "three-layer, feed-forward Radial Basis Function (RBF)" model, a materially different training regime than the backprop-MLP this patent describes. This is [unverified-mechanism — needs direct read; possible contradiction, not confirmed] and is not treated as fact pending a direct read of the actual IEEE/HICSS paper.