The ECJ has ruled with Judgment of Febru­ary 27, 2025 (Case C‑203/22 in the case of CK v. Magi­strat der Stadt Wien) spe­ci­fi­es what infor­ma­ti­on a con­trol­ler must pro­vi­de to a data sub­ject within the scope of the right of access under Art. 15 (1) (h) GDPR regar­ding the “logic invol­ved” in auto­ma­ted decis­i­on-making and pro­fil­ing must pro­vi­de. As a result, the con­trol­ler must pro­vi­de all infor­ma­ti­on that enables the data sub­ject to under­stand the data,

  • which per­so­nal data are pro­ce­s­sed in the con­text of auto­ma­ted decision-making
  • in which way they were used.

A com­plex mathe­ma­ti­cal for­mu­la (e.g. an algo­rithm) is just as insuf­fi­ci­ent as a detail­ed descrip­ti­on of each step of auto­ma­ted decision-making.

This judgment direct­ly con­cerns the right to infor­ma­ti­on in con­nec­tion with Auto­ma­ted decis­i­ons in indi­vi­du­al cases. It has an indi­rect effect on the right to infor­ma­ti­on as a who­le, becau­se its signi­fi­can­ce as a pri­or right is streng­the­ned: It ser­ves the exer­cise of fur­ther rights, which is why it must enable this exer­cise. This tends to lead to a broad inter­pre­ta­ti­on of the right to infor­ma­ti­on.

The spe­ci­fic case con­cer­ned the refu­sal of a mobi­le pho­ne con­tract due to an auto­ma­ted cre­dit check. Dun & Brad­street Austria had fai­led to pro­vi­de meaningful infor­ma­ti­on about the logic invol­ved in the cre­dit check despi­te being reque­sted to do so by the Austri­an data pro­tec­tion aut­ho­ri­ty. The Austri­an Fede­ral Admi­ni­stra­ti­ve Court came to the fol­lo­wing conclusion:

19 By decis­i­on of Octo­ber 23, 2019 […], the Fede­ral Admi­ni­stra­ti­ve Court found that D & B had vio­la­ted Artic­le 15(1)(h) GDPR by fai­ling to pro­vi­de CK with meaningful infor­ma­ti­on about the logic invol­ved in the auto­ma­ted decis­i­on-making based on CK’s per­so­nal data or at least by fai­ling to pro­vi­de suf­fi­ci­ent justi­fi­ca­ti­on as to why it was unable to pro­vi­de such information.

20 In its decis­i­on, the Fede­ral Admi­ni­stra­ti­ve Court sta­ted in par­ti­cu­lar that D & B’s expl­ana­ti­ons had not been suf­fi­ci­ent to put CK in its posi­ti­on, under­stand how the pro­ba­bi­li­ty of their future beha­vi­or (“score”) is pre­dic­ted. had been deter­mi­ned. This score had been com­mu­ni­ca­ted to CK by D & B with the indi­ca­ti­on that for its deter­mi­na­ti­on cer­tain socio-demo­gra­phic data from CK “weigh­ted equal­ly among them­sel­ves” had been made.

The ECJ sta­tes the following:

  • The “meaningful infor­ma­ti­on about the logic invol­ved” in auto­ma­ted decis­i­on-making inclu­des all of the fol­lo­wing Rele­vant infor­ma­ti­on on the pro­ce­du­re and prin­ci­ples auto­ma­ted processing:

    50 […] the inter­pre­ta­ti­on […] that “meaningful infor­ma­ti­on about the logic invol­ved” in auto­ma­ted decis­i­on-making within the mea­ning of this pro­vi­si­on all rele­vant infor­ma­ti­on on the method and prin­ci­ples of auto­ma­ted pro­ce­s­sing of per­so­nal data to achie­ve a spe­ci­fic result and that this infor­ma­ti­on must also be pro­vi­ded in a pre­cise, trans­pa­rent, com­pre­hen­si­ble and easi­ly acce­s­si­ble form due to the trans­pa­ren­cy requirement.

  • The infor­ma­ti­on must enable the data sub­ject to Effec­ti­ve exer­cise to exer­cise their rights under Art. 22 (3) GDPR (to express their point of view and to con­test the decision):

    53 As regards the spe­ci­fic right of access pro­vi­ded for in Art. 15 GDPR, accor­ding to the case law of the Court of Justi­ce, it must enable the data sub­ject to checkwhe­ther data con­cer­ning them right are and whe­ther they pro­ce­s­sed in a per­mis­si­ble man­ner become […].

    […]

    55 In par­ti­cu­lar, in the spe­ci­fic con­text of the adop­ti­on of a decis­i­on based sole­ly on auto­ma­ted pro­ce­s­sing, the main pur­po­se of the data subject’s right […] is to enable him or her to effec­tively exer­cise the rights to which he or she is entit­led under Artic­le 22(3) GDPR, name­ly that of right to sta­te their own posi­ti­on and the right to chall­enge the decis­i­on.

    […]

    58 […] it fol­lows that the right to “meaningful infor­ma­ti­on about the logic invol­ved” in auto­ma­ted decis­i­on-making within the mea­ning of this pro­vi­si­on is to be regard­ed as a right. Right to an expl­ana­ti­on of the pro­ce­du­re and prin­ci­ples is to be under­s­tood as the auto­ma­ted pro­ce­s­sing of the data subject’s per­so­nal data in order to arri­ve at a cer­tain result – such as a cre­dit­wort­hi­ness pro­fi­le – on the basis of this data. […]

  • Neither the mere trans­mis­si­on of a com­plex mathe­ma­ti­cal for­mu­la (such as a Algo­rithm) nor the Detail­ed descrip­ti­on of each step of auto­ma­ted decis­i­on-making meet the­se requi­re­ments. Rather, the data sub­ject must be able to under­stand, which per­so­nal data in the con­text of auto­ma­ted decis­i­on-making in which way used were:

    59 Neither the mere trans­mis­si­on of a com­plex mathe­ma­ti­cal for­mu­la (such as a Algo­rithm), the detail­ed descrip­ti­on of each step of auto­ma­ted decis­i­on-making meet the­se requi­re­ments, as neither is a suf­fi­ci­ent­ly pre­cise and com­pre­hen­si­ble explanation.

    […]

    61 The “meaningful infor­ma­ti­on about the logic invol­ved” in auto­ma­ted decis­i­on-making […] must the­r­e­fo­re descri­be the pro­cess and the prin­ci­ples that are spe­ci­fi­cal­ly applied in such a way that the data sub­ject can can under­stand which of their per­so­nal data has been used in the con­text of the auto­ma­ted decis­i­on-making in que­sti­on and in what waywit­hout the com­ple­xi­ty of the steps to be taken in the con­text of auto­ma­ted decis­i­on-making releasing the con­trol­ler from his obli­ga­ti­on to pro­vi­de explanations.

    62 As regards, spe­ci­fi­cal­ly, pro­fil­ing such as that at issue in the main pro­ce­e­dings, the refer­ring court could, in par­ti­cu­lar, con­sider it suf­fi­ci­ent­ly trans­pa­rent and com­pre­hen­si­ble to inform the data sub­ject, the ext­ent to which a devia­ti­on in the per­so­nal data taken into account would lead to a dif­fe­rent result. would have led.

  • If infor­ma­ti­on Busi­ness secrets or per­so­nal data of third par­ties the­se may have to be trans­mit­ted to the super­vi­so­ry aut­ho­ri­ty or the com­pe­tent court who must weigh up the oppo­sing rights and interests:

    73 […] a natio­nal court […] may con­sider that per­so­nal data must be trans­mit­ted to it by par­ties or third par­ties in order to enable it […] to weigh up the inte­rests invol­ved. That assess­ment may, whe­re appro­pria­te, lead it to aut­ho­ri­ze the dis­clo­sure to the other par­ty of all or part of the per­so­nal data thus trans­mit­ted to it […].

  • Natio­nal pro­vi­si­ons, such as Sec­tion 4 (6) DSG-AT in this case, which Exclude the right to infor­ma­ti­on across the boardif the infor­ma­ti­on would jeo­par­di­ze a busi­ness or trade secret, are not com­pa­ti­ble with Art. 15 GDPR com­pa­ti­ble. A blan­ket rest­ric­tion is inad­mis­si­ble becau­se the con­side­ra­ti­on must be made on a case-by-case basis:

    75 With regard to the need to deter­mi­ne this on a case-by-case basis, Artic­le 15(1)(h) GDPR in par­ti­cu­lar pre­clu­des the appli­ca­ti­on of a pro­vi­si­on such as Sec­tion 4(6) FADP, which in prin­ci­ple exclu­des the data subject’s right to infor­ma­ti­on pro­vi­ded for in Artic­le 15 GDPR if the infor­ma­ti­on would jeo­par­di­ze a busi­ness or trade secret of the con­trol­ler or a third par­ty. A Mem­ber Sta­te can­not con­clu­si­ve­ly pre­scri­be the result of a balan­cing of the oppo­sing rights and inte­rests to be car­ri­ed out on a case-by-case basis as pre­scri­bed by Uni­on law (cf. in this sen­se Judgment of Decem­ber 7, 2023, SCHUFA Hol­ding and Others [Scoring], C‑634/21, EU:C:2023:957, para. 70 and the case law cited therein).