http://decision.tcc-cci.gc.ca/tcc-cci/decisions/en/item/98322/index.do 
Le sage au piano v. The Queen (October 28, 2014 – 2014 TCC 319) was a companion case to one blogged earlier here where the applicant was denied an extension of time to file a notice of objection:
[1] The case of Le Sage au piano, limited partnership (the applicant), was heard on semi-common evidence with the application of Les Monarques complexe pour retraités Inc. (Les Monarques). Despite that some evidence was common to both files, for example, the companies belong to the same corporate group and the witnesses were the same, the evidence was different given the orders made in each file.
The principal distinction between the two cases was that in this case the addressing of the notice of assessment was defective:
[4] The applicant is a company whose headquarters are located at 465 Rue Bibeau, suite 600, Saint-Eustache, Quebec.
…
[11] On June 3, 2013, the ARQ assessed the applicant under the ETA for the period from October 1, 2009, to October 31, 2009 (the period at issue). The assessment dealt with the FMV of the phase 2 complex.
[12] It is worth noting that the notice of assessment was addressed to the applicant’s headquarters, at 465 Rue Bibeau, Saint-Eustache, Quebec, but that the suite number was not included.
That defect was found by the Tax Court to entitle the taxpayer to relief:
[41] Even though the Minister demonstrated that most of the mail in the file was received by the applicant despite the absence of the suite number, that does not mean that the address was complete.
[42] Furthermore, like the applicant noted, how is it that the suite number was on the correspondence sent by the ARQ to the applicant on January 8, 2014? The ARQ cannot have used the address stated on the notice of objection produced by counsel for the applicant because that address did not include the suite number. It is therefore likely that the address with the suite number is from the ARQ’s computer records. Indeed, I noted that the applicant, in the files for the phase 1 complex, included the suite number in its address.
[43] In my view, the respondent had to prove that the address used for mailing purposes was the correct address, which it did not do in this case. If the respondent had proven that the address provided by the applicant did not include the suite number, my finding would have been different. A taxpayer cannot argue that the address used by the ARQ is not correct if the ARQ uses the address provided by the taxpayer.
[44] As stated by Justice Noël in Scott, supra, a notice of assessment sent to a wrong address is equivalent to a notice of assessment that was not sent at all.
[45] Consequently, the application for an extension of time for filing a notice of objection is allowed.
The Tax Court also found that, in any event, the applicant also met all of the requirements to entitle it to the extension sought.
[46] In any event, in this case, in light of the facts, I am of the opinion that the applicant meets the conditions listed in subsection 304(5) of the ETA that makes it possible for the Court to allow an application for an extension of time for filing a notice of objection.