It'd be pretty hard to make the argument that we're not experiencing an impassioned bull market right now. Since the lows of four years ago, the S&P 500 Index (^GSPC -0.46%) has rallied more than 130%. Not only that, but the S&P sits at all-time highs and is enjoying the longest monthly rally since 2009, with April being the sixth straight month of advances. But even as Wall Street marches ever higher, achieving new highs, these three S&P components managed to lose -- big. 

There are only a handful of cardinal sins in the equities market. Many of them stem from dishonesty: fudging numbers, hiding material results off balance sheet, insider trading, raiding pension funds -- these are all relatively straightforward no-nos. But as Pitney Bowes (PBI -0.47%) learned the hard way today, so is cutting your dividend. Shares slumped 15.6% Tuesday after the business equipment company missed earnings estimates and cut its dividend in half. 

Diversified machinery mainstay Cummins (CMI -0.25%) is the second of today's laggards, losing 6.1% after announcing some sluggish earnings of its own. In a $20 billion company, you'd expect to be able to pinpoint an area or two that did OK in a given period. Not the case for Cummins, which saw revenues in all four major segments decrease, with earnings stumbling 40% as demand for engines powering mining operations stalled big-time. 

The last of the day's laggards is Marathon Petroleum (MPC 0.19%), which cratered 4.9% after reporting earnings for the first quarter. Oddly enough, it wasn't that earnings were bad -- in fact, results were in line with estimates. Marathon even bought back stock and paid a dividend in the most recent quarter. Today's slip has more to do with worries that refiners like Marathon will suffer through periods of depressed margins going forward.