Baccei v. United States, 632 F.3d 1140 (9th Cir. 2011)

(accountant who prepared estate's Form 706 attempted to file Form 4768 to extend filing deadline, but failed to enter appropriate extension period in space provided on Form and did not indicate on Form that payment extension necessary; taxes didn't get paid on time (because accountant thought extension had been filed), but IRS assessed penalty and interest; trial court's determination that substantial compliance doctrine inapplicable upheld; executor's reliance on accountant was not reasonable cause for failure to timely pay estate tax; actual tax due was more than 12 times size of estimated tax included on extension form).