delivered the opinion of the Court.
The appellant, a trust company organized under the laws of Pennsylvania, challenges a statute of the State as construed and applied in the assessment of a tax for the year 1930, denominated a tax on shares. From a settlement made against the company by the Department of Revenue an appeal was taken to the Court of Common Pleas of Dauphin County, which, after trial without a jury, entered judgment in favor of the Commonwealth.1 The Supreme Court of Pennsylvania affirmed the judgment.2 The appellant’s contention is that the Act, as so construed and applied by the Department and the courts, discriminates against United States Government bonds, bonds of federal instrumentalities, and national bank stocks, included in the appellant’s assets. The appellee replies that the tax is upon the shares of stock as such, and not upon the assets which represent their value; that, in fact, no tax whatever, much less a discriminatory tax, has been levied upon exempt assets of the company.
Prior to the year 1907 Pennsylvania trust companies were liable for what is known as a capital stock tax, levied upon the corporation. In the administration of *115that form of exaction certain securities, such as United States bonds and national bank shares, are eliminated from tax by deduction of their value from the value of the total assets of the corporations which own them. The deduction of exempt securities is made to avoid double taxation, the theory being that the shares issued by a corporation and its capital stock are identical, so that taxation of the one is taxation of the other.3
On June 13, 1907, the General Assembly adopted an act prescribing another method of taxation in the case of trust companies. Its pertinent provisions are copied in the margin.4 This statute in terms lays a tax upon shares rather than upon corporate assets. The value of each share is to be ascertained by adding the value of capital stock paid in, surplus, and undivided profits, and dividing the total by the number of outstanding shares. Thus the exaction is measured by the value of the con> pany’s net assets. This involves the exclusion of corporate liabilities from the measure of value to which the rate is to be applied.5 By successive amendments it was di*116rected that the value of each share of stock should be ascertained by adding together so much of the amount of capital stock paid in, surplus, and undivided profits as is not invested in the shares of stock of corporations liable to pay to the Commonwealth a capital stock tax or tax on shares, or relieved from the payment of capital stock tax or tax on shares, and dividing the sum by the number of outstanding shares.6 These amendments were combined with the original act, in a single statute of April 25, 1929.7
Obviously, the theory of the amendments was that as trust companies, so long as they had been liable for capital stock tax, had been exempted from payment of tax reckoned upon assets which had already paid a tax or were exempt from tax, — that is, the stock of corporations of Pennsylvania which had paid a capital stock tax or whose shares had been taxed or had been exempted from tax,— it was proper, in levying a tax upon the shares of trust companies reckoned upon the net assets of those companies, to exempt from such net assets so much thereof as represented shares of corporations which had already paid a tax or, under the policy of the Commonwealth, had been exempted.
The impost as laid by the Act of 1907 was a true tax on shares and not a tax upon the assets of trust companies. Such an exaction is not a tax upon United States securities owned by the corporation whose shares are taxed or upon securities exempt from taxation because issued by instrumentalities of the Federal Government.8
*117It will be observed that by the amendments to the Act of 1907 the measure of the tax is not in any sense the value of the shares as such, but a value reflected by so much of the net assets as is not represented by shares of Pennsylvania corporations already taxed or exempt from tax. In the administration of the act as amended the procedure which has been followed and approved9 is first to deduct the liabilities from the total assets, thus arriving at the net assets. The theory has been that exempt shares owned by the trust company must be shown to have been actually purchased out of capital stock or surplus in order to obtain a deduction of their full value from the gross assets. If the company is unable to demonstrate that they were purchased in that manner, then a proportional method of deduction is adopted. This is to apply to the taxed value of all such exempt securities a fraction the numerator of which is the net assets and the denominator the gross assets. The result of applying this fraction to the taxed value of exempt shares is said to give the proportion of those exempt shares attributable to capital, surplus, and undivided profits, and the quotient is accordingly deducted from the value of the net assets to obtain the measure of the tax on all the shares, and this, divided by the number of outstanding shares, gives the measure of the tax for each share. In the instant case the trust company held amongst its assets shares of Pennsylvania corporations, exempt from tax, of the value of $135,787. It also held shares of the Philadelphia National Bank of the value of $20,202. These were found by the Department of Revenue to have been taxed at a total taxable value of $71,373. Applying the fractional formula mentioned, it was found that $8,886 of their taxable value should be attributed to capital, surplus and undivided profits, and deducted from the *118amount of the net assets. As the net assets had been, ascertained to be $467,714 the deduction brought this figure down to $458,028, to which the rate of tax of five mills was applied.
It should be stated that under the Act the corporation is required to make a report as the basis for the calculation of the tax, and, upon that report, the Department of Revenue settles the tax which is assessed against the corporation. The trust company, and not the stockholders, is liable in the first instance for the tax. Though given the right to pay the tax from its funds or to collect the amount from its stockholders, neither the company nor the Commonwealth is given any lien upon the stock for the amount of the tax. As the obligation to pay the Commonwealth is that of the company, its interest and its right to contest are beyond question.
In specifications of objection filed with its appeal from the tax settlement in the Court of Common Pleas, the trust company insisted that all exempt shares (including the shares of the Philadelphia National Bank) should be deducted from the gross assets in full. This would exempt their full value rather than a proportion of their taxed value as ascertained by the use of the proportional method above described. The further objection was made that the method of settlement adopted resulted in discrimination against exempt securities issued by the United States or other federal instrumentalities, and that these should have been deducted at their full value from the gross assets before any computation of the tax. The Common Pleas Court overruled these objections (without discussing the treatment of the national bank shares), saying, with respect to United States bonds and like exempt securities, that as the tax was a tax upon shares, and not upon the assets of the trust company, those securities had not in fact been taxed. In affirming the judgment the Supreme Court of Pennsylvania said that as *119the specifications of objections had not covered the point as to national bank shares and the court below had not discussed that matter it was not open in the appellate court. As respects United States bonds, and other Federal securities, it concurred in the view of the lower court.
First. The appellant insists that as merely a portion of the net assets of the corporation is taken as the basis or measure of the tax, it cannot be upon the shares as shares. The appellee relies upon the statement of the Supreme Court of Pennsylvania that the levy is upon the shares and not upon assets. The appellant asks us to find to the contrary. We give great weight to the characterization of a tax, or the interpretation of a state law, emanating from the highest court of the State, but where a federal question is involved we are not bound by the label attached to the tax or the character ascribed to the law. We must determine for ourselves the true nature of the tax by ascertaining its operation and effect.10
It is clear that the tax is not measured by each shareholder’s aliquot proportion of all the assets of the company. If amongst those assets are found shares of stock of Pennsylvania corporations which, or whose shares, have been declared exempt by the State, this exemption is effected in the instant case by taking them wholly or partially out of the net assets which are the base for the tax. The appellant says this demonstrates that the tax is one upon assets. If the appellant is right the exaction operates as a discrimination against Government securities and other assets exempt under federal law. Missouri Insurance Co. v. Gehner, 281 U. S. 313. If the tax is one truly upon that independent property evidenced by the ownership of a share of corporate stock its collection does not discriminate against United States securities.11
*120We think that the issue of discrimination is not to be resolved by a choice between the two contentions as to the nature of the tax. The point is that the State has chosen a portion only of the net assets of the corporation as a measure of the tax, whether the exaction be from the company or its shareholders. The State has exempted certain assets on the theory that to measure the tax in part by their value would in effect be to tax them twice. If to measure the shareholder’s tax by inclusion of these taxed or exempted securities found amongst the company’s assets would be to tax the shareholder in virtue of the company’s ownership of those securities, it seems clear that to refuse to exempt United States securities from the measure of the tax is to lay a tax reckoned upon their value. To put it otherwise, if to exclude securities already taxed or exempted from tax pursuant to the policy of the Commonwealth avoids double taxation, to include United States securities in the measure of the tax seems inevitably to increase the burden of the tax by reason of their ownership. If the burden of the tax be lifted in respect of some securities (as it is by confession from those issued by certain Pennsylvania corporations) it must necessarily fall on the remaining securities owned by the company. If the tax is lifted from the shares of certain trust companies because those companies own only stocks already taxed or. relieved from taxation by the State, and shares in other trust companies are taxed amongst whose assets there are United States bonds or other securities entitled to exemption because issued by federal instrumentalities, which are figured in the base of the tax, it is impossible to avoid the conclusion that the law discriminates in favor of the former and against the latter solely by reason of ownership of such federal securities.
Second. It is indisputable that the shares of stock of the Philadelphia National Bank owned by the appellant *121were included in the base or measure of the tax. It is undenied that these shares had been taxed to the trust company, as permitted by R. S. 5219, and in accordance with the applicable statutes of Pennsylvania;12 and it must be conceded that having once been taxed to their owner, the trust company, they may not again be made the base or measure of a tax to that company’s stockholders. Bank of California v. Richardson, 248 U. S. 476. The trial court seems to have excluded them upon the theory that they were not within the intent of the taxing statute, which the court thought meant to exempt only shares of Pennsylvania corporations which had been taxed or relieved from tax by local law. This view the trial court appears to have abandoned in a later case,13 where it was held that stock of a federal reserve bank was within the meaning of the Pennsylvania act and entitled to exemption. This later decision was affirmed by the Supreme Court of Pennsylvania.14
We are told that the matter is not open here for the reason that it was not raised on appeal to the Dauphin County court, was not discussed by that court, and consequently the Supreme Court refused to consider it. Whether the point was in fact raised in the court below is itself a federal question, and we are bound to examine the record to resolve it.15 It appears that in the specifications of objection filed in Dauphin County court complaint was made that whereas there should have been a flat deduction of all shares of corporations theretofore taxed or exempted from tax, shares of the Philadelphia *122National Bank were included in shares granted only a proportional deduction. It further appears that in accordance with Pennsylvania practice, after the trial of the cause to the court without a jury the appellant submitted requests for conclusions of law. Amongst these were requests 10 and 16, which referred specifically to the Philadelphia National Bank stock, and severally requested the court to find (a) that these shares having been once taxed under another act, to the trust company as owner, could not be taxed a second time, and (b) that the failure to deduct the full value of the shares from the net assets of the trust company operated to discriminate and impose a tax upon the shares of stock in violation of R. S. 5219, they having once been taxed under another statute. The court answered both, these requests in writing, “ Refused.” The refusal of the requests was made the subject of exceptions which quoted the requests and the answers of the court verbatim. The exceptions were overruled by the court and errors were assigned to the Supreme Court of Pennsylvania to the overruling of the exceptions applicable to the refusal of the requests in question, which were again quoted verbatim, with the answer of the court to the request and the overruling of the corresponding exception. In addition to these assignments of error the appellant in the statement of questions involved, required by the rules of the Supreme Court of Pennsylvania to be made a part of the brief on appeal, amongst others set forth the following question: “Are assets consisting of national bank shares to be eliminated from consideration in determining the taxable value to which the rate of tax is to be applied by deducting their actual value from the value of the net assets? Answer of the court below No.”
We think that notwithstanding the Dauphin County court, in its opinion, failed to discuss this matter, as the Supreme Court of Pennsylvania points out, the question was sharply presented to that court and decided by it, and *123that the rights of the appellant were specifically preserved and pressed at every stage of the proceeding. We find, therefore, that the question is here for decision. It might well be disposed of by reference to what has already been said with respect to bonds of the United States and like securities. The discrimination here disclosed is, however, more obvious than in the case of the other securities mentioned. The Commonwealth of Pennsylvania elected to exempt certain shares of stock of its own corporations because they had already been taxed. It exempted them because to include them in the base would be in effect to tax them a second time. The shares of the Philadelphia National Bank had also been taxed pursuant to R. S. 5219, and if they were to be treated on an equal footing with shares of domestic corporations the State was bound to afford them a similar exemption from a second exaction.
Third. The appellant argues that if, as declared by the Supreme Court of Pennsylvania, the tax is one upon shares as such, it cannot be laid or collected by the Commonwealth in respect of 166 shares of stock of the appellant which by confession are owned by individual citizens and residents of states other than Pennsylvania, for the reason that such shares have no taxable situs in Pennsylvania. In view of the grounds of our decision we find it unnecessary to pass upon this contention.
The judgment must be reversed and the cause remanded for further proceedings not inconsistent with this opinion.
Reversed.
38 Dauphin County Reports, 22.
315 Pa. 429; 173 Atl. 309.
Commonwealth v. Standard Oil Co., 101 Pa. 119, 145; Commonwealth v. Fall Brook Coal Co., 156 Pa. 488; 26 Atl. 1071; Commonwealth v. Pennsylvania R. Co., 297 Pa. 308, 314; 147 Atl. 242; Commonwealth v. Eastern Securities Co., 309 Pa. 44; 163 Atl. 157.
“Section 1. That from and after the passage of this act, every company . . . shall . . . make to the Auditor General a report in writing . . . setting forth the full number of shares of the capital stock subscribed for or issued by such company, and the actual value thereof, which shall be ascertained as hereinafter provided; and thereupon it shall be the duty of the Auditor General to assess such shares for taxation at the rate of five mills upon each dollar of the actual value thereof, the actual value of each share of stock to be ascertained and fixed by adding together the amount of capital stock paid in, the surplus and undivided profits, and dividing this amount by the number of shares. . . .” [L. 1907, Act No. 512, p. 640.]
Commonwealth v. Union Trust Co., 237 Pa. 353, 355, 356; 85 Atl. 461.
Act of July 11, 1923, P. L. 1071-72. Act of May 7, 1927, P. L. 853, 855.
P. L. 673. The Act of April 9, 1929, P. L. 343, §§ 807 and 1705 (the so-called Fiscal Code), did not alter the substance of the law but merely affected the executive agencies which were to administer it.
Van Allen v. Assessors, 3 Wall. 573; Cleveland Trust Co. v. Lander, 184 U. S. 111; Des Moines National Bank v. Fairweather, 263 U. S. 103.
Commonwealth v. Hazelwood Savings & Trust Co., 271 Pa. 375; 114 Atl. 368.
Senior v. Braden, 295 U. S. 422, 429.
See note 8, supra.
Act of July 15, 1897, P. L. 292, as amended by Act of April 25, 1929, P. L. 677.
Commonwealth v. Provident Trust Co., 40 Dauphin County (Pa.), 146, 177.
319 Pa. 385; 180 Atl. 16.
Carter v. Texas, 177 U. S. 442, 447; Ward v. Love County, 253 U. S. 17, 22.