Why BrainChip, HT&E, Platinum, and Whitehaven Coal are dropping

The S&P/ASX 200 Index (ASX: XJO) is on course to start the week with a gain. In afternoon trade, the benchmark index is up 0.3% to 7,465 points.

Four ASX shares that have failed to follow the market higher today are listed below. Here’s why they are dropping:

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