Thursday is the last day for conference committee debate on financial regulatory reform. Both House and Senate negotiators are seeking to hammer out the differences between their two bills, determining the shape of the final measure that, if approved, would be sent to President Obama for signature. Here's what's at stake in this landmark day in a months-long legislative battle to reform the way Wall Street does business and prevent another crash.

• Resist Lobbyists  Reuters's Andy Sullivan writes of the much-discussed Volcker Rule and derivatives rules, "Wall Street lobbyists have been unable to kill both proposals as Democrats ride a wave of public disgust at the industry over the damage to the economy and employment from the financial crisis of 2008. Still, the members of the committee are likely to soften their toughest proposals to retain the support of centrist lawmakers whose votes will be needed for the merged bill to clear both chambers of Congress before it is sent to Obama."

• Make Derivative Markets Transparent  The New York Times calls derivative regulation "arguably the most important issue for big banks because real reform will crimp their huge profits from derivatives deal-making. It also is arguably the most important one for the public. The largely unregulated, multitrillion-dollar market in derivatives fed the bubble, intensified the bust and led to the bailouts. Unreformed, it will do so again. The final bill must ensure that derivatives are traded on transparent exchanges and processed through third-party clearinghouses to guarantee payment in case of default."

• Should Banks Have to Spin Off Derivatives Business?  The Washington Post's David Cho reports, "Democratic leaders pressured Sen. Blanche Lincoln (D-Ark.) Wednesday to scale back a proposal that would force big banks to spin off their derivatives businesses, highlighting a conflict that has the potential to crack Democratic support behind the massive regulatory reform bill as it nears final passage. ... Her refusal to strike a deal is dividing liberal Democrats supporting the proposal and moderates who want it removed. The issue is expected to be in the spotlight Thursday as the House and Senate seek to reconcile their versions of the bill."

• Close The Loopholes  Time's Mark Wilson sighs, "Congress, as part of the financial reform legislation, is working on an exemption that would allow State Street to continue creating and investing in the conduits that nearly led to its demise. ... Welcome to the wonderful world of financial reform, where rules are set and then quickly it is determined what firms get to ignore them." Wilson explains past loopholes and those in the current legislation.

• Prevent Future Bailouts...and Bankruptcy  Reuters' Kevin Drawbaugh explains the delicate dance. "End the idea that some financial firms are 'too big to fail.' Avoid a repeat of 2008, when the Bush administration launched costly taxpayer bailouts of firms such as AIG but did not bail out Lehman Brothers. Lehman's subsequent bankruptcy froze capital markets." But at the same time, "Congress wants a middle ground between bailouts and bankruptcy. Firms would have to keep 'funeral plans' on file that describe how they could be shut down quickly."

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