The opinion of the court was delivered by
Mountain, J.Petitioner filed a claim for occupational hearing loss six years after retiring from his employment with respondent corporation. As the Workmen’s Compensation Act was then written, this time span exceeded the permissible period within which such a claim was required to be filed. Two months before his claim was heard, however, a statutory amendment abrogated the time limitation. The issue before us is whether the amendment applies and thus saves petitioner’s claim.
It was stipulated that petitioner, Louis Panzino, retired from respondent’s employ on March 31, 1966; that during the period of his employment he had been exposed to loud noise and had suffered a 54% binaural loss. It was not until the late summer of 1972, more than six years after the em*301ployment terminated, that Panzino discovered that his hearing loss was work-related. He filed his claim September 14, 1972. At that time the relevant limitations statute, N. J. S. A. 34:15-34, provided that claims for compensable occupational disability must be filed within two years of the employee’s last exposure during the course of employment, or within one year of discovery, whichever was longer; and that furthermore a claim would be “forever barred” unless presented within five years from the date of last exposure. An amendment to this statute,1 effective July 3, 1974, eliminated all time limitation requirements except “that where a claimant knew the nature of the disability and its relation to the employment,” the petition must be filed “within 2 years after the date on which the claimant first had such konwledge . . .” This claimant’s petition was filed within a month of his discovery that his hearing impairment was work-related.
On September 12, 1974, the Judge of Compensation ruled that Panzino was entitled to prevail, holding that he came within the favor of the statutory amendment. An award was entered in the sum of $4,320. On appeal the Appellate Division reversed. 135 N. J. Super. 206 (1975). It held that the amendment should be given only prospective application and that to give it retrospective effect would be to impair respondent’s vested right to impose the bar of the earlier time limitation. This Court granted certification. 68 N. J. 487 (1975).
We first consider whether or not the amendatory enactment was intended to have retrospective operation. The Sponsor’s Statement attached to the bill as introduced in the Assembly read as follows:
Occupational diseases are often of such an insidious nature that they do not become evident until years after exposure to the cause thereof. This bill memorializes this fact by abrogating the burdensome and *302arbitrary time restrictions presently in effect within which a claim for compensation must be filed, and which in fact may easily lapse before even the symptoms of disease are evident. As here prescribed, a claim would be permitted within 2 years after the claimant had actual knowledge of the nature of the disability and its relation to the employment.
Of the various materials that may reveal legislative intent, one of the most instructive is a statement by the sponsor of the act.
[T]he expressions of the sponsor of the bill normally reveal a legislative intent more significant than that revealed by those of a more casual legislative adherent. In this context, the significant legislative intent may well be the actual intent of the former. [Dickerson, The Interpretation and Application of Statutes 73 (1975)]
In the course of deliberations on a bill, legislators look to its sponsor as well as to the representatives of the committee having charge of it, as one who is expected to be particularly well informed about its purpose, meaning, and intended effect. In recognition of this reality of legislative practice, courts give consideration to statements made by a bill’s sponsor on grounds similar to those relied on to support the use of statements made by the committeeman in charge of the bill. [2A Sutherland, Statutes and Statutory Construction § 48.15, at 221-22 (4th ed. 1973)]
The sponsor’s statement here rather clearly identifies the mischief sought to be corrected. Existing time restrictions upon initiating claims have been found to be “burdensome” and “arbitrary.” Experience has revealed that by their very nature occupational diseases often do not become manifest until years after exposure. This Court’s decision in Kane v. Durotest Corp., 37 N. J. 552 (1962), identified the rigors of a statutory time limit. There the petitioner’s decedent had contracted beryllium poisoning from which she ultimately died. She did not, however, become aware of the existence of the disease until seven and one-half years after leaving respondent’s employ. Because this exceeded the five-year term within which such a claim was required to be filed, her suit was barred. The result seemed then, and seems now, to have been unjust. There we said,
*303If the five-year limitation for prosecution of the compensation action occasionally operates harshly and lengthening of the period is considered desirable, the appeal for such change must be to the Legisture. [37 N. J. at 556]
The relief afforded by the new amendment can be seen as a legislative response to such an appeal, signifying an intent that claims for occupational disease shall be honored if filed within two years of discovery.
Purther, it has long been axiomatic that the Workmen’s Compensation Act is to be liberally construed. Torres v. Trenton Times Newspaper, 64 N. J. 458, 461 (1974); Petrozzino v. Monroe Calculating Machine Co., Inc., 47 N. J. 577, 580 (1966); Close v. Kordulak Bros., 44 N. J. 589, 604 (1965). Bearing this in mind, being aware of the mischief sought to be remedied and always conscious of the beneficent purposes of this important social legislation, we perceive no reason why the Legislature would have wished to place any greater limitation upon the reach of the statute than can sensibly be drawn from its language. Accordingly we conclude that the enactment should be read to cover any claimant who files a petition within two years of the date on which he learns the nature of his disability and its relation to his employment.
Of course, to read the statute in this way sanctions petitioner’s claim, unless, as so read, the enactment is unconstitutional. The claim was filed within a month of Panzino’s discovery that his affliction — of which he had long been conscious — was work-related. Respondent argues that our giving the amendment this interpretation results in an unconstitutional deprivation of its "vested right” to take advantage of the statutory time limits in effect when the claim was filed. According to this argument, for which respondent finds support in this Court’s decision in State v. Standard Oil Co., 5 N. J. 281 (1950), aff’d sub nom. Standard Oil Co. v. State of New Jersey, 341 U. S. 428, 71 S. Ct. 822, 95 L. Ed. 1078 (1951), respondent could not constitutionally be deprived of the right to assert the *304bar of the time limitations set forth in the statute in effect when petitioner filed his claim. The filing in fact took place on September 14, 1972, by which date the applicable period had already expired. Stated somewhat differently, under this rationale respondent’s defense may be characterized as the assertion of a vested right which could not be lost either by legislative or judicial intervention without impairing due process guarantees. Therefore, respondent contends, the fact that the statute was amended after the claim was filed, but before hearing, could have no effect upon its vested right to plead the statute; the passage of time had extinguished the remedy and petitioner’s right of action died with it.
A constitutional challenge to state legislation on the ground that it impairs or destroys a vested right generally implicates the due process clause of the Eourteenth Amendment. Rothman v. Rothman, 65 N. J. 219, 225 (1974). The Supreme Court of the United States considered such a challenge in Chase Securities Corporation v. Donaldson, 325 U. S. 304, 65 S. Ct. 1137, 89 L. Ed. 1628 (1945). There a statute of the State of Minnesota had the effect of lifting the bar of the statute of limitations in a pending litigation. Appellant contended that to permit the new enactment to affect its rights would amount to taking its property without due process of law. In an opinion written by Justice Jackson the Court disagreed. It confirmed its earlier holding in Campbell v. Holt, 115 U. S. 620, 6 S. Ct. 209, 29 L. Ed. 483 (1885) and stated,
[C]ertainly it cannot be said that lifting the bar of a statute of limitation so as to restore a remedy lost through mere lapse of time is per se an offense against the Fourteenth Amendment. [325 U. S. at 316, 65 S. Ct. at 1143, 89 L. Ed. at 1636]
In State v. Standard Oil Co., supra, an escheat case, this Court considered the effect of the running of the statute of limitations upon a contractual obligation — a chose in action. We there said that at the expiration of the statu*305tory period, not only did the remedy expire hut also the right was extinguished. Acknowledging that in view of the Supreme Court’s decisions in Chase Securities Corporation v. Donaldson and Campbell v. Holt, both supra, there was no violation of the Fourteenth Amendment, our opinion nevertheless went on to say that
[t]he principle is embedded in our jurisprudence that where a right of action has become barred under existing law, the statutory defense constitutes a vested right which is proof against legislative impairment. [5 N. J. at 293]
We do not choose to accord this statement the comprehensive amplitude suggested by respondent. Rather we think it should be confined to the particular issue before the Court in that ease, i. e., the effect of lapse of time upon a claim sounding in contract. The plaintiff’s claim in the case before us does not spring from contract; it is a right born of statute. See N. J. S. A. 34:15-30. We are satisfied that the Legislature, by virtue of the 1974 amendment, has simply enlarged the availability of this statutory right to compensation for occupational disease by removing the five-year limitation period.
Because Panzino’s claim is so evidently grounded in the statute, it cannot be characterized as deriving from the contract of employment. The notion that rights such as this are contractual has hitherto been considered and emphatically rejected.
The hollowness of the ring of “contract” becomes obvious when we tap it against the fact that the Compensation Act became binding upon employers and employees whose employment contracts antedated adoption of the act, * * * and, at least until an injury, the parties are bound by even radical and substantive changes in the act made after the entry into the employment contract.
The analogy to contract is often a handy aid for the analysis of a specific problem, just as a paper tube may sometimes be an aid to hearing, but “contract” no more accurately describes the rights and duties of an employer and employee under the Workmen’s Compensation Act than a paper tube corrects deafness. [McAllister v. Board *306of Ed. of Kearny, 79 N. J. Super. 249, 260 (App. Div. 1963), aff’d, 42 N. J. 56 (1964)]
The position we take today is strengthened by recalling the manner in which our' courts have treated time requirements set forth in the Workmen’s Compensation Act. They have not been considered as ordinary statutes of limitation, but rather as jurisdictional prerequisites to agency action. In order to invoke the jurisdiction of the Workmen’s Compensation Division, it has been as necessary to show that the petition was filed within the statutory time span as to show that the injury arose out of and in the course of employment. Schwarz v. Federal Shipbuilding and Dry Dock Co., 16 N. J. 243, 248 (1954).
[T]ke filing of the claim within a year is a jurisdictional fact, and not what the complainant calls a statute of limitations, the pleading of which might or might not be enjoined in a court of equity. [Miller v. Beller Electric Supply Co., 100 N. J. Eq. 444, 445 (Ch. 1927)]
See also Davis v. State, 44 N. J. Super. 435, 441-42 (App. Div. 1957); Riccioni v. American Cyanamid Co., 26 N. J. Super. 1, 5 (App. Div.), certif. den. 13 N. J. 289 (1953); Valentine v. Walter Kidde & Co., 136 N. J. L. 292, 293 (Sup. Ct. 1947).
Respondent’s defense, then, was not a bar made available by a statute of limitations, but rather the Compensation Court’s lack of jurisdiction. Thus it can logically be said that the 1974 amendment does not revive an expired claim; instead it merely enlarges the agency’s jurisdiction. What could not be successfully claimed at the time the suit was filed had become permissible at the time the case was heard and the defense of lack of jurisdiction no longer existed as a bar to the relief sought by petitioner.
It is, accordingly, our conclusion that the statutory amendment under consideration must be interpreted retroactively as described above, and that as so construed it must be sustained. The judgment of the Appellate Division is re*307versed and the judgment of the Division of Workmen’s Compensation is reinstated.
L. 1974, c. 65.