I did not review SPQ SRP (you can review on Sedar - passed by BOD May 8, Approved June 11, 2009), but would be surprised if there is a 20% exception similar to KWG. I think the KWG SRP was tailored specifically to their deal with Cliff. Also, if there was such an exception Cliff would have disclosed it in their circular. Here is the relevant exerpt from their circular:

Shareholder Rights Plan
On May 8, 2009, the Board of Directors adopted a Shareholder Rights Plan that was approved by Shareholders on June 11, 2009. The Offer is not a Permitted Bid for the purposes of the Shareholder Rights Plan.

Accordingly, in order for the Offer to proceed, the Shareholder Rights Plan must be terminated or some action must be taken by the Board of Directors or by a securities commission or court of competent jurisdiction to remove the effect of the
Shareholder Rights Plan and permit the Offer to proceed. See Section 16 of the Circular, “Shareholder Rights Plan”.

The Offeror believes that at the Expiry Time, Spider and its Board of Directors and Shareholders will have had more than adequate time to fully consider the Offer and any available alternative transactions and to determine whether to deposit their Common Shares under the Offer.

The Offer is being made on the condition, among others, that the Shareholder Rights Plan does not and will not adversely affect the Offer or Spider either before or on consummation of the Offer or the purchase of Common Shares of Spider under a Compulsory Acquisition or consummation of any Second Stage Transaction. See Section 4
of the Offer to Purchase, “Conditions of the Offer”.

I could be wrong, but I don't think it was a legal requirement in Canada to disclose their purchases, where to my understanding you only need to disclose once you reach 10% or more. In the US, I think, it is 5%, which is getting very close. Maybe that is what triggered it, as tomorrow if they continue purchasing they will exceed that limit..