Wiseman v. Perrey, 2013 BCSC 904 is a decision containing a good summary on various aspects of costs, ranging from offers to settle, special costs, and the apportionment of costs between parties who have been ” largely successful” at trial.
The general rule is that costs follow the event and that the successful party is entitled to receive assessed costs and disbursements.
There were two court a tigons tried at the same time in the Wiseman case. In one the defendant was mostly successful, and in the other, the defendant was entirely successful.
The Law on Apportionment of Costs
In Chaster (Guardian ad litem) v. LeBlanc (2008), 51 C.P.C. (6th) 184 (B.C.S.C.), Hinkson J., as he then was, approved and followed the test set out in Fotheringham v. Fotheringham (2001), 13 C.P.C. (5th) 302 (B.C.S.C.), appeal refused  B.C.J. No. 1872, where Bouck J. stated:
Gold [Gold v. Gold (1993), 82 B.C.L.R. (2d) 180 (B.C.C.A.)] now seems to say that substantial success in an action should be decided by the trial judge looking at the various matters in dispute and weighing their relative importance. The words “substantial success” are not defined. For want of a better measure, since success, a passing grade, is around 50% or better, substantial success is about 75% or better. That does not mean a court must descend into a meticulous mathematical examination of the matters in dispute and assign a percentage to each matter. Rather, it is meant to serve as a rough and ready guide when looked at all the disputed matters globally.
Application of the Gold Principle and Rule 57(9) to this Action
Based on the above interpretation of Rules 57(9), 57(15) and Gold, a decision to award or not award costs after a trial might follow a four step inquiry.
1. First, by focusing on the “matters in dispute” at the trial. These may or may not include “issues” explicitly mentioned in the pleadings.
2. Second, by assessing the weight or importance of those “matters” to the parties.
3. Third, by doing a global determination with respect to all the matters in dispute and determining which party “substantially succeeded,” overall and therefore won the event.
4. Fourth, where one party “substantially succeeded,” a consideration of whether there are reasons to “otherwise order” that the winning party be deprived of his or her costs and each side then bear their own costs.
(at paras. 45-56)
 Of similar effect are the decisions in Citta Construction Ltd. v. E. Lane Holdings Ltd. et al.,  B.C.J. No. 392, Chaster, supra, and Moro v. El Mantari,  B.C.J. No. 811.
 In Mawdsley v Meshen (2011), 22 B.C.L.R. (5th) 168 , Ballance J. stated:
The definitive authority is Sutherland v. The Attorney General of Canada, 2008 BCCA 27. There, the Court of Appeal surveyed the authorities, including its important earlier decision in B.C. (Gov’t.) v. Worthington (Canada) Inc.,  1 WWR 1, 29 B.C.L.R. (2d) 145 (C.A.). In Worthington, the Court of Appeal had clarified that the purpose of apportioning costs is to effect a just result between the parties where proceedings have been prolonged by issues which the party, who would otherwise be entitled to costs, has lost.
Returning to Sutherland, at para. 31, the Court of Appeal set out the test for the apportionment of costs:
The test for the apportionment of costs under Rule 57(15) can be set out as follows:
(1) the party seeking apportionment must establish that there are separate and discrete issues upon which the ultimately unsuccessful party succeeded at trial;
(2) there must be a basis on which the trial judge can identify the time attributable to the trial of these separate issues;
(3) it must be shown that apportionment would effect a just result.
(at paras. 42-43)