Schwab's response is that they are sticking to their interpretation:
I am happy to confirm I spoke to our Client Reporting and Security Services Team about your previous message! I can confirm the information Schwab has been provided for the Rights Exercise Offer for ARCAM AB 17RTSF is that this offer is for qualified institutional buyers and each right would entitle the holder to purchase five (5) new ordinary shares.
Does anyone have a link that supports the idea of all shareholders and 5 to 1 instead of 1 to 5?